xref: /openbmc/linux/net/ipv6/addrconf.c (revision 56fc709b7a9fe191173dc772a881e180458db517)
1 /*
2  *	IPv6 Address [auto]configuration
3  *	Linux INET6 implementation
4  *
5  *	Authors:
6  *	Pedro Roque		<roque@di.fc.ul.pt>
7  *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
8  *
9  *	This program is free software; you can redistribute it and/or
10  *      modify it under the terms of the GNU General Public License
11  *      as published by the Free Software Foundation; either version
12  *      2 of the License, or (at your option) any later version.
13  */
14 
15 /*
16  *	Changes:
17  *
18  *	Janos Farkas			:	delete timer on ifdown
19  *	<chexum@bankinf.banki.hu>
20  *	Andi Kleen			:	kill double kfree on module
21  *						unload.
22  *	Maciej W. Rozycki		:	FDDI support
23  *	sekiya@USAGI			:	Don't send too many RS
24  *						packets.
25  *	yoshfuji@USAGI			:       Fixed interval between DAD
26  *						packets.
27  *	YOSHIFUJI Hideaki @USAGI	:	improved accuracy of
28  *						address validation timer.
29  *	YOSHIFUJI Hideaki @USAGI	:	Privacy Extensions (RFC3041)
30  *						support.
31  *	Yuji SEKIYA @USAGI		:	Don't assign a same IPv6
32  *						address on a same interface.
33  *	YOSHIFUJI Hideaki @USAGI	:	ARCnet support
34  *	YOSHIFUJI Hideaki @USAGI	:	convert /proc/net/if_inet6 to
35  *						seq_file.
36  *	YOSHIFUJI Hideaki @USAGI	:	improved source address
37  *						selection; consider scope,
38  *						status etc.
39  */
40 
41 #define pr_fmt(fmt) "IPv6: " fmt
42 
43 #include <linux/errno.h>
44 #include <linux/types.h>
45 #include <linux/kernel.h>
46 #include <linux/sched/signal.h>
47 #include <linux/socket.h>
48 #include <linux/sockios.h>
49 #include <linux/net.h>
50 #include <linux/inet.h>
51 #include <linux/in6.h>
52 #include <linux/netdevice.h>
53 #include <linux/if_addr.h>
54 #include <linux/if_arp.h>
55 #include <linux/if_arcnet.h>
56 #include <linux/if_infiniband.h>
57 #include <linux/route.h>
58 #include <linux/inetdevice.h>
59 #include <linux/init.h>
60 #include <linux/slab.h>
61 #ifdef CONFIG_SYSCTL
62 #include <linux/sysctl.h>
63 #endif
64 #include <linux/capability.h>
65 #include <linux/delay.h>
66 #include <linux/notifier.h>
67 #include <linux/string.h>
68 #include <linux/hash.h>
69 
70 #include <net/net_namespace.h>
71 #include <net/sock.h>
72 #include <net/snmp.h>
73 
74 #include <net/6lowpan.h>
75 #include <net/firewire.h>
76 #include <net/ipv6.h>
77 #include <net/protocol.h>
78 #include <net/ndisc.h>
79 #include <net/ip6_route.h>
80 #include <net/addrconf.h>
81 #include <net/tcp.h>
82 #include <net/ip.h>
83 #include <net/netlink.h>
84 #include <net/pkt_sched.h>
85 #include <net/l3mdev.h>
86 #include <linux/if_tunnel.h>
87 #include <linux/rtnetlink.h>
88 #include <linux/netconf.h>
89 #include <linux/random.h>
90 #include <linux/uaccess.h>
91 #include <asm/unaligned.h>
92 
93 #include <linux/proc_fs.h>
94 #include <linux/seq_file.h>
95 #include <linux/export.h>
96 
97 /* Set to 3 to get tracing... */
98 #define ACONF_DEBUG 2
99 
100 #if ACONF_DEBUG >= 3
101 #define ADBG(fmt, ...) printk(fmt, ##__VA_ARGS__)
102 #else
103 #define ADBG(fmt, ...) do { if (0) printk(fmt, ##__VA_ARGS__); } while (0)
104 #endif
105 
106 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
107 
108 #define IPV6_MAX_STRLEN \
109 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
110 
111 static inline u32 cstamp_delta(unsigned long cstamp)
112 {
113 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
114 }
115 
116 static inline s32 rfc3315_s14_backoff_init(s32 irt)
117 {
118 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
119 	u64 tmp = (900000 + prandom_u32() % 200001) * (u64)irt;
120 	do_div(tmp, 1000000);
121 	return (s32)tmp;
122 }
123 
124 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
125 {
126 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
127 	u64 tmp = (1900000 + prandom_u32() % 200001) * (u64)rt;
128 	do_div(tmp, 1000000);
129 	if ((s32)tmp > mrt) {
130 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
131 		tmp = (900000 + prandom_u32() % 200001) * (u64)mrt;
132 		do_div(tmp, 1000000);
133 	}
134 	return (s32)tmp;
135 }
136 
137 #ifdef CONFIG_SYSCTL
138 static int addrconf_sysctl_register(struct inet6_dev *idev);
139 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
140 #else
141 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
142 {
143 	return 0;
144 }
145 
146 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
147 {
148 }
149 #endif
150 
151 static void ipv6_regen_rndid(struct inet6_dev *idev);
152 static void ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
153 
154 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
155 static int ipv6_count_addresses(const struct inet6_dev *idev);
156 static int ipv6_generate_stable_address(struct in6_addr *addr,
157 					u8 dad_count,
158 					const struct inet6_dev *idev);
159 
160 /*
161  *	Configured unicast address hash table
162  */
163 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
164 static DEFINE_SPINLOCK(addrconf_hash_lock);
165 
166 static void addrconf_verify(void);
167 static void addrconf_verify_rtnl(void);
168 static void addrconf_verify_work(struct work_struct *);
169 
170 static struct workqueue_struct *addrconf_wq;
171 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
172 
173 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
174 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
175 
176 static void addrconf_type_change(struct net_device *dev,
177 				 unsigned long event);
178 static int addrconf_ifdown(struct net_device *dev, int how);
179 
180 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
181 						  int plen,
182 						  const struct net_device *dev,
183 						  u32 flags, u32 noflags);
184 
185 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
186 static void addrconf_dad_work(struct work_struct *w);
187 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id);
188 static void addrconf_dad_run(struct inet6_dev *idev);
189 static void addrconf_rs_timer(unsigned long data);
190 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
191 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
192 
193 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
194 				struct prefix_info *pinfo);
195 
196 static struct ipv6_devconf ipv6_devconf __read_mostly = {
197 	.forwarding		= 0,
198 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
199 	.mtu6			= IPV6_MIN_MTU,
200 	.accept_ra		= 1,
201 	.accept_redirects	= 1,
202 	.autoconf		= 1,
203 	.force_mld_version	= 0,
204 	.mldv1_unsolicited_report_interval = 10 * HZ,
205 	.mldv2_unsolicited_report_interval = HZ,
206 	.dad_transmits		= 1,
207 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
208 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
209 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
210 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
211 	.use_tempaddr		= 0,
212 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
213 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
214 	.regen_max_retry	= REGEN_MAX_RETRY,
215 	.max_desync_factor	= MAX_DESYNC_FACTOR,
216 	.max_addresses		= IPV6_MAX_ADDRESSES,
217 	.accept_ra_defrtr	= 1,
218 	.accept_ra_from_local	= 0,
219 	.accept_ra_min_hop_limit= 1,
220 	.accept_ra_pinfo	= 1,
221 #ifdef CONFIG_IPV6_ROUTER_PREF
222 	.accept_ra_rtr_pref	= 1,
223 	.rtr_probe_interval	= 60 * HZ,
224 #ifdef CONFIG_IPV6_ROUTE_INFO
225 	.accept_ra_rt_info_min_plen = 0,
226 	.accept_ra_rt_info_max_plen = 0,
227 #endif
228 #endif
229 	.proxy_ndp		= 0,
230 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
231 	.disable_ipv6		= 0,
232 	.accept_dad		= 1,
233 	.suppress_frag_ndisc	= 1,
234 	.accept_ra_mtu		= 1,
235 	.stable_secret		= {
236 		.initialized = false,
237 	},
238 	.use_oif_addrs_only	= 0,
239 	.ignore_routes_with_linkdown = 0,
240 	.keep_addr_on_down	= 0,
241 	.seg6_enabled		= 0,
242 #ifdef CONFIG_IPV6_SEG6_HMAC
243 	.seg6_require_hmac	= 0,
244 #endif
245 	.enhanced_dad           = 1,
246 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
247 	.disable_policy		= 0,
248 };
249 
250 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
251 	.forwarding		= 0,
252 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
253 	.mtu6			= IPV6_MIN_MTU,
254 	.accept_ra		= 1,
255 	.accept_redirects	= 1,
256 	.autoconf		= 1,
257 	.force_mld_version	= 0,
258 	.mldv1_unsolicited_report_interval = 10 * HZ,
259 	.mldv2_unsolicited_report_interval = HZ,
260 	.dad_transmits		= 1,
261 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
262 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
263 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
264 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
265 	.use_tempaddr		= 0,
266 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
267 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
268 	.regen_max_retry	= REGEN_MAX_RETRY,
269 	.max_desync_factor	= MAX_DESYNC_FACTOR,
270 	.max_addresses		= IPV6_MAX_ADDRESSES,
271 	.accept_ra_defrtr	= 1,
272 	.accept_ra_from_local	= 0,
273 	.accept_ra_min_hop_limit= 1,
274 	.accept_ra_pinfo	= 1,
275 #ifdef CONFIG_IPV6_ROUTER_PREF
276 	.accept_ra_rtr_pref	= 1,
277 	.rtr_probe_interval	= 60 * HZ,
278 #ifdef CONFIG_IPV6_ROUTE_INFO
279 	.accept_ra_rt_info_min_plen = 0,
280 	.accept_ra_rt_info_max_plen = 0,
281 #endif
282 #endif
283 	.proxy_ndp		= 0,
284 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
285 	.disable_ipv6		= 0,
286 	.accept_dad		= 1,
287 	.suppress_frag_ndisc	= 1,
288 	.accept_ra_mtu		= 1,
289 	.stable_secret		= {
290 		.initialized = false,
291 	},
292 	.use_oif_addrs_only	= 0,
293 	.ignore_routes_with_linkdown = 0,
294 	.keep_addr_on_down	= 0,
295 	.seg6_enabled		= 0,
296 #ifdef CONFIG_IPV6_SEG6_HMAC
297 	.seg6_require_hmac	= 0,
298 #endif
299 	.enhanced_dad           = 1,
300 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
301 	.disable_policy		= 0,
302 };
303 
304 /* Check if link is ready: is it up and is a valid qdisc available */
305 static inline bool addrconf_link_ready(const struct net_device *dev)
306 {
307 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
308 }
309 
310 static void addrconf_del_rs_timer(struct inet6_dev *idev)
311 {
312 	if (del_timer(&idev->rs_timer))
313 		__in6_dev_put(idev);
314 }
315 
316 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
317 {
318 	if (cancel_delayed_work(&ifp->dad_work))
319 		__in6_ifa_put(ifp);
320 }
321 
322 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
323 				  unsigned long when)
324 {
325 	if (!timer_pending(&idev->rs_timer))
326 		in6_dev_hold(idev);
327 	mod_timer(&idev->rs_timer, jiffies + when);
328 }
329 
330 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
331 				   unsigned long delay)
332 {
333 	in6_ifa_hold(ifp);
334 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
335 		in6_ifa_put(ifp);
336 }
337 
338 static int snmp6_alloc_dev(struct inet6_dev *idev)
339 {
340 	int i;
341 
342 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
343 	if (!idev->stats.ipv6)
344 		goto err_ip;
345 
346 	for_each_possible_cpu(i) {
347 		struct ipstats_mib *addrconf_stats;
348 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
349 		u64_stats_init(&addrconf_stats->syncp);
350 	}
351 
352 
353 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
354 					GFP_KERNEL);
355 	if (!idev->stats.icmpv6dev)
356 		goto err_icmp;
357 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
358 					   GFP_KERNEL);
359 	if (!idev->stats.icmpv6msgdev)
360 		goto err_icmpmsg;
361 
362 	return 0;
363 
364 err_icmpmsg:
365 	kfree(idev->stats.icmpv6dev);
366 err_icmp:
367 	free_percpu(idev->stats.ipv6);
368 err_ip:
369 	return -ENOMEM;
370 }
371 
372 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
373 {
374 	struct inet6_dev *ndev;
375 	int err = -ENOMEM;
376 
377 	ASSERT_RTNL();
378 
379 	if (dev->mtu < IPV6_MIN_MTU)
380 		return ERR_PTR(-EINVAL);
381 
382 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
383 	if (!ndev)
384 		return ERR_PTR(err);
385 
386 	rwlock_init(&ndev->lock);
387 	ndev->dev = dev;
388 	INIT_LIST_HEAD(&ndev->addr_list);
389 	setup_timer(&ndev->rs_timer, addrconf_rs_timer,
390 		    (unsigned long)ndev);
391 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
392 
393 	if (ndev->cnf.stable_secret.initialized)
394 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
395 	else
396 		ndev->cnf.addr_gen_mode = ipv6_devconf_dflt.addr_gen_mode;
397 
398 	ndev->cnf.mtu6 = dev->mtu;
399 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
400 	if (!ndev->nd_parms) {
401 		kfree(ndev);
402 		return ERR_PTR(err);
403 	}
404 	if (ndev->cnf.forwarding)
405 		dev_disable_lro(dev);
406 	/* We refer to the device */
407 	dev_hold(dev);
408 
409 	if (snmp6_alloc_dev(ndev) < 0) {
410 		ADBG(KERN_WARNING
411 			"%s: cannot allocate memory for statistics; dev=%s.\n",
412 			__func__, dev->name);
413 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
414 		dev_put(dev);
415 		kfree(ndev);
416 		return ERR_PTR(err);
417 	}
418 
419 	if (snmp6_register_dev(ndev) < 0) {
420 		ADBG(KERN_WARNING
421 			"%s: cannot create /proc/net/dev_snmp6/%s\n",
422 			__func__, dev->name);
423 		goto err_release;
424 	}
425 
426 	/* One reference from device. */
427 	refcount_set(&ndev->refcnt, 1);
428 
429 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
430 		ndev->cnf.accept_dad = -1;
431 
432 #if IS_ENABLED(CONFIG_IPV6_SIT)
433 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
434 		pr_info("%s: Disabled Multicast RS\n", dev->name);
435 		ndev->cnf.rtr_solicits = 0;
436 	}
437 #endif
438 
439 	INIT_LIST_HEAD(&ndev->tempaddr_list);
440 	ndev->desync_factor = U32_MAX;
441 	if ((dev->flags&IFF_LOOPBACK) ||
442 	    dev->type == ARPHRD_TUNNEL ||
443 	    dev->type == ARPHRD_TUNNEL6 ||
444 	    dev->type == ARPHRD_SIT ||
445 	    dev->type == ARPHRD_NONE) {
446 		ndev->cnf.use_tempaddr = -1;
447 	} else
448 		ipv6_regen_rndid(ndev);
449 
450 	ndev->token = in6addr_any;
451 
452 	if (netif_running(dev) && addrconf_link_ready(dev))
453 		ndev->if_flags |= IF_READY;
454 
455 	ipv6_mc_init_dev(ndev);
456 	ndev->tstamp = jiffies;
457 	err = addrconf_sysctl_register(ndev);
458 	if (err) {
459 		ipv6_mc_destroy_dev(ndev);
460 		snmp6_unregister_dev(ndev);
461 		goto err_release;
462 	}
463 	/* protected by rtnl_lock */
464 	rcu_assign_pointer(dev->ip6_ptr, ndev);
465 
466 	/* Join interface-local all-node multicast group */
467 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
468 
469 	/* Join all-node multicast group */
470 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
471 
472 	/* Join all-router multicast group if forwarding is set */
473 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
474 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
475 
476 	return ndev;
477 
478 err_release:
479 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
480 	ndev->dead = 1;
481 	in6_dev_finish_destroy(ndev);
482 	return ERR_PTR(err);
483 }
484 
485 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
486 {
487 	struct inet6_dev *idev;
488 
489 	ASSERT_RTNL();
490 
491 	idev = __in6_dev_get(dev);
492 	if (!idev) {
493 		idev = ipv6_add_dev(dev);
494 		if (IS_ERR(idev))
495 			return NULL;
496 	}
497 
498 	if (dev->flags&IFF_UP)
499 		ipv6_mc_up(idev);
500 	return idev;
501 }
502 
503 static int inet6_netconf_msgsize_devconf(int type)
504 {
505 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
506 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
507 	bool all = false;
508 
509 	if (type == NETCONFA_ALL)
510 		all = true;
511 
512 	if (all || type == NETCONFA_FORWARDING)
513 		size += nla_total_size(4);
514 #ifdef CONFIG_IPV6_MROUTE
515 	if (all || type == NETCONFA_MC_FORWARDING)
516 		size += nla_total_size(4);
517 #endif
518 	if (all || type == NETCONFA_PROXY_NEIGH)
519 		size += nla_total_size(4);
520 
521 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
522 		size += nla_total_size(4);
523 
524 	return size;
525 }
526 
527 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
528 				      struct ipv6_devconf *devconf, u32 portid,
529 				      u32 seq, int event, unsigned int flags,
530 				      int type)
531 {
532 	struct nlmsghdr  *nlh;
533 	struct netconfmsg *ncm;
534 	bool all = false;
535 
536 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
537 			flags);
538 	if (!nlh)
539 		return -EMSGSIZE;
540 
541 	if (type == NETCONFA_ALL)
542 		all = true;
543 
544 	ncm = nlmsg_data(nlh);
545 	ncm->ncm_family = AF_INET6;
546 
547 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
548 		goto nla_put_failure;
549 
550 	if (!devconf)
551 		goto out;
552 
553 	if ((all || type == NETCONFA_FORWARDING) &&
554 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
555 		goto nla_put_failure;
556 #ifdef CONFIG_IPV6_MROUTE
557 	if ((all || type == NETCONFA_MC_FORWARDING) &&
558 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
559 			devconf->mc_forwarding) < 0)
560 		goto nla_put_failure;
561 #endif
562 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
563 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
564 		goto nla_put_failure;
565 
566 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
567 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
568 			devconf->ignore_routes_with_linkdown) < 0)
569 		goto nla_put_failure;
570 
571 out:
572 	nlmsg_end(skb, nlh);
573 	return 0;
574 
575 nla_put_failure:
576 	nlmsg_cancel(skb, nlh);
577 	return -EMSGSIZE;
578 }
579 
580 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
581 				  int ifindex, struct ipv6_devconf *devconf)
582 {
583 	struct sk_buff *skb;
584 	int err = -ENOBUFS;
585 
586 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
587 	if (!skb)
588 		goto errout;
589 
590 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
591 					 event, 0, type);
592 	if (err < 0) {
593 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
594 		WARN_ON(err == -EMSGSIZE);
595 		kfree_skb(skb);
596 		goto errout;
597 	}
598 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
599 	return;
600 errout:
601 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
602 }
603 
604 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
605 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
606 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
607 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
608 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
609 };
610 
611 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
612 				     struct nlmsghdr *nlh,
613 				     struct netlink_ext_ack *extack)
614 {
615 	struct net *net = sock_net(in_skb->sk);
616 	struct nlattr *tb[NETCONFA_MAX+1];
617 	struct inet6_dev *in6_dev = NULL;
618 	struct net_device *dev = NULL;
619 	struct netconfmsg *ncm;
620 	struct sk_buff *skb;
621 	struct ipv6_devconf *devconf;
622 	int ifindex;
623 	int err;
624 
625 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
626 			  devconf_ipv6_policy, extack);
627 	if (err < 0)
628 		return err;
629 
630 	if (!tb[NETCONFA_IFINDEX])
631 		return -EINVAL;
632 
633 	err = -EINVAL;
634 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
635 	switch (ifindex) {
636 	case NETCONFA_IFINDEX_ALL:
637 		devconf = net->ipv6.devconf_all;
638 		break;
639 	case NETCONFA_IFINDEX_DEFAULT:
640 		devconf = net->ipv6.devconf_dflt;
641 		break;
642 	default:
643 		dev = dev_get_by_index(net, ifindex);
644 		if (!dev)
645 			return -EINVAL;
646 		in6_dev = in6_dev_get(dev);
647 		if (!in6_dev)
648 			goto errout;
649 		devconf = &in6_dev->cnf;
650 		break;
651 	}
652 
653 	err = -ENOBUFS;
654 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
655 	if (!skb)
656 		goto errout;
657 
658 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
659 					 NETLINK_CB(in_skb).portid,
660 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
661 					 NETCONFA_ALL);
662 	if (err < 0) {
663 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
664 		WARN_ON(err == -EMSGSIZE);
665 		kfree_skb(skb);
666 		goto errout;
667 	}
668 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
669 errout:
670 	if (in6_dev)
671 		in6_dev_put(in6_dev);
672 	if (dev)
673 		dev_put(dev);
674 	return err;
675 }
676 
677 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
678 				      struct netlink_callback *cb)
679 {
680 	struct net *net = sock_net(skb->sk);
681 	int h, s_h;
682 	int idx, s_idx;
683 	struct net_device *dev;
684 	struct inet6_dev *idev;
685 	struct hlist_head *head;
686 
687 	s_h = cb->args[0];
688 	s_idx = idx = cb->args[1];
689 
690 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
691 		idx = 0;
692 		head = &net->dev_index_head[h];
693 		rcu_read_lock();
694 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
695 			  net->dev_base_seq;
696 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
697 			if (idx < s_idx)
698 				goto cont;
699 			idev = __in6_dev_get(dev);
700 			if (!idev)
701 				goto cont;
702 
703 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
704 						       &idev->cnf,
705 						       NETLINK_CB(cb->skb).portid,
706 						       cb->nlh->nlmsg_seq,
707 						       RTM_NEWNETCONF,
708 						       NLM_F_MULTI,
709 						       NETCONFA_ALL) < 0) {
710 				rcu_read_unlock();
711 				goto done;
712 			}
713 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
714 cont:
715 			idx++;
716 		}
717 		rcu_read_unlock();
718 	}
719 	if (h == NETDEV_HASHENTRIES) {
720 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
721 					       net->ipv6.devconf_all,
722 					       NETLINK_CB(cb->skb).portid,
723 					       cb->nlh->nlmsg_seq,
724 					       RTM_NEWNETCONF, NLM_F_MULTI,
725 					       NETCONFA_ALL) < 0)
726 			goto done;
727 		else
728 			h++;
729 	}
730 	if (h == NETDEV_HASHENTRIES + 1) {
731 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
732 					       net->ipv6.devconf_dflt,
733 					       NETLINK_CB(cb->skb).portid,
734 					       cb->nlh->nlmsg_seq,
735 					       RTM_NEWNETCONF, NLM_F_MULTI,
736 					       NETCONFA_ALL) < 0)
737 			goto done;
738 		else
739 			h++;
740 	}
741 done:
742 	cb->args[0] = h;
743 	cb->args[1] = idx;
744 
745 	return skb->len;
746 }
747 
748 #ifdef CONFIG_SYSCTL
749 static void dev_forward_change(struct inet6_dev *idev)
750 {
751 	struct net_device *dev;
752 	struct inet6_ifaddr *ifa;
753 
754 	if (!idev)
755 		return;
756 	dev = idev->dev;
757 	if (idev->cnf.forwarding)
758 		dev_disable_lro(dev);
759 	if (dev->flags & IFF_MULTICAST) {
760 		if (idev->cnf.forwarding) {
761 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
762 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
763 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
764 		} else {
765 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
766 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
767 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
768 		}
769 	}
770 
771 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
772 		if (ifa->flags&IFA_F_TENTATIVE)
773 			continue;
774 		if (idev->cnf.forwarding)
775 			addrconf_join_anycast(ifa);
776 		else
777 			addrconf_leave_anycast(ifa);
778 	}
779 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
780 				     NETCONFA_FORWARDING,
781 				     dev->ifindex, &idev->cnf);
782 }
783 
784 
785 static void addrconf_forward_change(struct net *net, __s32 newf)
786 {
787 	struct net_device *dev;
788 	struct inet6_dev *idev;
789 
790 	for_each_netdev(net, dev) {
791 		idev = __in6_dev_get(dev);
792 		if (idev) {
793 			int changed = (!idev->cnf.forwarding) ^ (!newf);
794 			idev->cnf.forwarding = newf;
795 			if (changed)
796 				dev_forward_change(idev);
797 		}
798 	}
799 }
800 
801 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
802 {
803 	struct net *net;
804 	int old;
805 
806 	if (!rtnl_trylock())
807 		return restart_syscall();
808 
809 	net = (struct net *)table->extra2;
810 	old = *p;
811 	*p = newf;
812 
813 	if (p == &net->ipv6.devconf_dflt->forwarding) {
814 		if ((!newf) ^ (!old))
815 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
816 						     NETCONFA_FORWARDING,
817 						     NETCONFA_IFINDEX_DEFAULT,
818 						     net->ipv6.devconf_dflt);
819 		rtnl_unlock();
820 		return 0;
821 	}
822 
823 	if (p == &net->ipv6.devconf_all->forwarding) {
824 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
825 
826 		net->ipv6.devconf_dflt->forwarding = newf;
827 		if ((!newf) ^ (!old_dflt))
828 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
829 						     NETCONFA_FORWARDING,
830 						     NETCONFA_IFINDEX_DEFAULT,
831 						     net->ipv6.devconf_dflt);
832 
833 		addrconf_forward_change(net, newf);
834 		if ((!newf) ^ (!old))
835 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
836 						     NETCONFA_FORWARDING,
837 						     NETCONFA_IFINDEX_ALL,
838 						     net->ipv6.devconf_all);
839 	} else if ((!newf) ^ (!old))
840 		dev_forward_change((struct inet6_dev *)table->extra1);
841 	rtnl_unlock();
842 
843 	if (newf)
844 		rt6_purge_dflt_routers(net);
845 	return 1;
846 }
847 
848 static void addrconf_linkdown_change(struct net *net, __s32 newf)
849 {
850 	struct net_device *dev;
851 	struct inet6_dev *idev;
852 
853 	for_each_netdev(net, dev) {
854 		idev = __in6_dev_get(dev);
855 		if (idev) {
856 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
857 
858 			idev->cnf.ignore_routes_with_linkdown = newf;
859 			if (changed)
860 				inet6_netconf_notify_devconf(dev_net(dev),
861 							     RTM_NEWNETCONF,
862 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
863 							     dev->ifindex,
864 							     &idev->cnf);
865 		}
866 	}
867 }
868 
869 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
870 {
871 	struct net *net;
872 	int old;
873 
874 	if (!rtnl_trylock())
875 		return restart_syscall();
876 
877 	net = (struct net *)table->extra2;
878 	old = *p;
879 	*p = newf;
880 
881 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
882 		if ((!newf) ^ (!old))
883 			inet6_netconf_notify_devconf(net,
884 						     RTM_NEWNETCONF,
885 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
886 						     NETCONFA_IFINDEX_DEFAULT,
887 						     net->ipv6.devconf_dflt);
888 		rtnl_unlock();
889 		return 0;
890 	}
891 
892 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
893 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
894 		addrconf_linkdown_change(net, newf);
895 		if ((!newf) ^ (!old))
896 			inet6_netconf_notify_devconf(net,
897 						     RTM_NEWNETCONF,
898 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
899 						     NETCONFA_IFINDEX_ALL,
900 						     net->ipv6.devconf_all);
901 	}
902 	rtnl_unlock();
903 
904 	return 1;
905 }
906 
907 #endif
908 
909 /* Nobody refers to this ifaddr, destroy it */
910 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
911 {
912 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
913 
914 #ifdef NET_REFCNT_DEBUG
915 	pr_debug("%s\n", __func__);
916 #endif
917 
918 	in6_dev_put(ifp->idev);
919 
920 	if (cancel_delayed_work(&ifp->dad_work))
921 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
922 			  ifp);
923 
924 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
925 		pr_warn("Freeing alive inet6 address %p\n", ifp);
926 		return;
927 	}
928 	ip6_rt_put(ifp->rt);
929 
930 	kfree_rcu(ifp, rcu);
931 }
932 
933 static void
934 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
935 {
936 	struct list_head *p;
937 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
938 
939 	/*
940 	 * Each device address list is sorted in order of scope -
941 	 * global before linklocal.
942 	 */
943 	list_for_each(p, &idev->addr_list) {
944 		struct inet6_ifaddr *ifa
945 			= list_entry(p, struct inet6_ifaddr, if_list);
946 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
947 			break;
948 	}
949 
950 	list_add_tail_rcu(&ifp->if_list, p);
951 }
952 
953 static u32 inet6_addr_hash(const struct in6_addr *addr)
954 {
955 	return hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT);
956 }
957 
958 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
959 			       struct net_device *dev)
960 {
961 	unsigned int hash = inet6_addr_hash(addr);
962 	struct inet6_ifaddr *ifp;
963 
964 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
965 		if (!net_eq(dev_net(ifp->idev->dev), net))
966 			continue;
967 		if (ipv6_addr_equal(&ifp->addr, addr)) {
968 			if (!dev || ifp->idev->dev == dev)
969 				return true;
970 		}
971 	}
972 	return false;
973 }
974 
975 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
976 {
977 	unsigned int hash;
978 	int err = 0;
979 
980 	spin_lock(&addrconf_hash_lock);
981 
982 	/* Ignore adding duplicate addresses on an interface */
983 	if (ipv6_chk_same_addr(dev_net(dev), &ifa->addr, dev)) {
984 		ADBG("ipv6_add_addr: already assigned\n");
985 		err = -EEXIST;
986 		goto out;
987 	}
988 
989 	/* Add to big hash table */
990 	hash = inet6_addr_hash(&ifa->addr);
991 	hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
992 
993 out:
994 	spin_unlock(&addrconf_hash_lock);
995 
996 	return err;
997 }
998 
999 /* On success it returns ifp with increased reference count */
1000 
1001 static struct inet6_ifaddr *
1002 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
1003 	      const struct in6_addr *peer_addr, int pfxlen,
1004 	      int scope, u32 flags, u32 valid_lft, u32 prefered_lft,
1005 	      bool can_block, struct netlink_ext_ack *extack)
1006 {
1007 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
1008 	struct net *net = dev_net(idev->dev);
1009 	struct inet6_ifaddr *ifa = NULL;
1010 	struct rt6_info *rt = NULL;
1011 	int err = 0;
1012 	int addr_type = ipv6_addr_type(addr);
1013 
1014 	if (addr_type == IPV6_ADDR_ANY ||
1015 	    addr_type & IPV6_ADDR_MULTICAST ||
1016 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
1017 	     addr_type & IPV6_ADDR_LOOPBACK))
1018 		return ERR_PTR(-EADDRNOTAVAIL);
1019 
1020 	if (idev->dead) {
1021 		err = -ENODEV;			/*XXX*/
1022 		goto out;
1023 	}
1024 
1025 	if (idev->cnf.disable_ipv6) {
1026 		err = -EACCES;
1027 		goto out;
1028 	}
1029 
1030 	/* validator notifier needs to be blocking;
1031 	 * do not call in atomic context
1032 	 */
1033 	if (can_block) {
1034 		struct in6_validator_info i6vi = {
1035 			.i6vi_addr = *addr,
1036 			.i6vi_dev = idev,
1037 			.extack = extack,
1038 		};
1039 
1040 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1041 		err = notifier_to_errno(err);
1042 		if (err < 0)
1043 			goto out;
1044 	}
1045 
1046 	ifa = kzalloc(sizeof(*ifa), gfp_flags);
1047 	if (!ifa) {
1048 		ADBG("ipv6_add_addr: malloc failed\n");
1049 		err = -ENOBUFS;
1050 		goto out;
1051 	}
1052 
1053 	rt = addrconf_dst_alloc(idev, addr, false);
1054 	if (IS_ERR(rt)) {
1055 		err = PTR_ERR(rt);
1056 		rt = NULL;
1057 		goto out;
1058 	}
1059 
1060 	if (net->ipv6.devconf_all->disable_policy ||
1061 	    idev->cnf.disable_policy)
1062 		rt->dst.flags |= DST_NOPOLICY;
1063 
1064 	neigh_parms_data_state_setall(idev->nd_parms);
1065 
1066 	ifa->addr = *addr;
1067 	if (peer_addr)
1068 		ifa->peer_addr = *peer_addr;
1069 
1070 	spin_lock_init(&ifa->lock);
1071 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1072 	INIT_HLIST_NODE(&ifa->addr_lst);
1073 	ifa->scope = scope;
1074 	ifa->prefix_len = pfxlen;
1075 	ifa->flags = flags;
1076 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1077 	if (!(flags & IFA_F_NODAD))
1078 		ifa->flags |= IFA_F_TENTATIVE;
1079 	ifa->valid_lft = valid_lft;
1080 	ifa->prefered_lft = prefered_lft;
1081 	ifa->cstamp = ifa->tstamp = jiffies;
1082 	ifa->tokenized = false;
1083 
1084 	ifa->rt = rt;
1085 
1086 	ifa->idev = idev;
1087 	in6_dev_hold(idev);
1088 
1089 	/* For caller */
1090 	refcount_set(&ifa->refcnt, 1);
1091 
1092 	rcu_read_lock_bh();
1093 
1094 	err = ipv6_add_addr_hash(idev->dev, ifa);
1095 	if (err < 0) {
1096 		rcu_read_unlock_bh();
1097 		goto out;
1098 	}
1099 
1100 	write_lock(&idev->lock);
1101 
1102 	/* Add to inet6_dev unicast addr list. */
1103 	ipv6_link_dev_addr(idev, ifa);
1104 
1105 	if (ifa->flags&IFA_F_TEMPORARY) {
1106 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1107 		in6_ifa_hold(ifa);
1108 	}
1109 
1110 	in6_ifa_hold(ifa);
1111 	write_unlock(&idev->lock);
1112 
1113 	rcu_read_unlock_bh();
1114 
1115 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1116 out:
1117 	if (unlikely(err < 0)) {
1118 		if (rt)
1119 			ip6_rt_put(rt);
1120 		if (ifa) {
1121 			if (ifa->idev)
1122 				in6_dev_put(ifa->idev);
1123 			kfree(ifa);
1124 		}
1125 		ifa = ERR_PTR(err);
1126 	}
1127 
1128 	return ifa;
1129 }
1130 
1131 enum cleanup_prefix_rt_t {
1132 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1133 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1134 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1135 };
1136 
1137 /*
1138  * Check, whether the prefix for ifp would still need a prefix route
1139  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1140  * constants.
1141  *
1142  * 1) we don't purge prefix if address was not permanent.
1143  *    prefix is managed by its own lifetime.
1144  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1145  * 3) if there are no addresses, delete prefix.
1146  * 4) if there are still other permanent address(es),
1147  *    corresponding prefix is still permanent.
1148  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1149  *    don't purge the prefix, assume user space is managing it.
1150  * 6) otherwise, update prefix lifetime to the
1151  *    longest valid lifetime among the corresponding
1152  *    addresses on the device.
1153  *    Note: subsequent RA will update lifetime.
1154  **/
1155 static enum cleanup_prefix_rt_t
1156 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1157 {
1158 	struct inet6_ifaddr *ifa;
1159 	struct inet6_dev *idev = ifp->idev;
1160 	unsigned long lifetime;
1161 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1162 
1163 	*expires = jiffies;
1164 
1165 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1166 		if (ifa == ifp)
1167 			continue;
1168 		if (!ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1169 				       ifp->prefix_len))
1170 			continue;
1171 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1172 			return CLEANUP_PREFIX_RT_NOP;
1173 
1174 		action = CLEANUP_PREFIX_RT_EXPIRE;
1175 
1176 		spin_lock(&ifa->lock);
1177 
1178 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1179 		/*
1180 		 * Note: Because this address is
1181 		 * not permanent, lifetime <
1182 		 * LONG_MAX / HZ here.
1183 		 */
1184 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1185 			*expires = ifa->tstamp + lifetime * HZ;
1186 		spin_unlock(&ifa->lock);
1187 	}
1188 
1189 	return action;
1190 }
1191 
1192 static void
1193 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt)
1194 {
1195 	struct rt6_info *rt;
1196 
1197 	rt = addrconf_get_prefix_route(&ifp->addr,
1198 				       ifp->prefix_len,
1199 				       ifp->idev->dev,
1200 				       0, RTF_GATEWAY | RTF_DEFAULT);
1201 	if (rt) {
1202 		if (del_rt)
1203 			ip6_del_rt(rt);
1204 		else {
1205 			if (!(rt->rt6i_flags & RTF_EXPIRES))
1206 				rt6_set_expires(rt, expires);
1207 			ip6_rt_put(rt);
1208 		}
1209 	}
1210 }
1211 
1212 
1213 /* This function wants to get referenced ifp and releases it before return */
1214 
1215 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1216 {
1217 	int state;
1218 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1219 	unsigned long expires;
1220 
1221 	ASSERT_RTNL();
1222 
1223 	spin_lock_bh(&ifp->lock);
1224 	state = ifp->state;
1225 	ifp->state = INET6_IFADDR_STATE_DEAD;
1226 	spin_unlock_bh(&ifp->lock);
1227 
1228 	if (state == INET6_IFADDR_STATE_DEAD)
1229 		goto out;
1230 
1231 	spin_lock_bh(&addrconf_hash_lock);
1232 	hlist_del_init_rcu(&ifp->addr_lst);
1233 	spin_unlock_bh(&addrconf_hash_lock);
1234 
1235 	write_lock_bh(&ifp->idev->lock);
1236 
1237 	if (ifp->flags&IFA_F_TEMPORARY) {
1238 		list_del(&ifp->tmp_list);
1239 		if (ifp->ifpub) {
1240 			in6_ifa_put(ifp->ifpub);
1241 			ifp->ifpub = NULL;
1242 		}
1243 		__in6_ifa_put(ifp);
1244 	}
1245 
1246 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1247 		action = check_cleanup_prefix_route(ifp, &expires);
1248 
1249 	list_del_rcu(&ifp->if_list);
1250 	__in6_ifa_put(ifp);
1251 
1252 	write_unlock_bh(&ifp->idev->lock);
1253 
1254 	addrconf_del_dad_work(ifp);
1255 
1256 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1257 
1258 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1259 
1260 	if (action != CLEANUP_PREFIX_RT_NOP) {
1261 		cleanup_prefix_route(ifp, expires,
1262 			action == CLEANUP_PREFIX_RT_DEL);
1263 	}
1264 
1265 	/* clean up prefsrc entries */
1266 	rt6_remove_prefsrc(ifp);
1267 out:
1268 	in6_ifa_put(ifp);
1269 }
1270 
1271 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *ift)
1272 {
1273 	struct inet6_dev *idev = ifp->idev;
1274 	struct in6_addr addr, *tmpaddr;
1275 	unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_tstamp, age;
1276 	unsigned long regen_advance;
1277 	int tmp_plen;
1278 	int ret = 0;
1279 	u32 addr_flags;
1280 	unsigned long now = jiffies;
1281 	long max_desync_factor;
1282 	s32 cnf_temp_preferred_lft;
1283 
1284 	write_lock_bh(&idev->lock);
1285 	if (ift) {
1286 		spin_lock_bh(&ift->lock);
1287 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1288 		spin_unlock_bh(&ift->lock);
1289 		tmpaddr = &addr;
1290 	} else {
1291 		tmpaddr = NULL;
1292 	}
1293 retry:
1294 	in6_dev_hold(idev);
1295 	if (idev->cnf.use_tempaddr <= 0) {
1296 		write_unlock_bh(&idev->lock);
1297 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1298 		in6_dev_put(idev);
1299 		ret = -1;
1300 		goto out;
1301 	}
1302 	spin_lock_bh(&ifp->lock);
1303 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1304 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1305 		spin_unlock_bh(&ifp->lock);
1306 		write_unlock_bh(&idev->lock);
1307 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1308 			__func__);
1309 		in6_dev_put(idev);
1310 		ret = -1;
1311 		goto out;
1312 	}
1313 	in6_ifa_hold(ifp);
1314 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1315 	ipv6_try_regen_rndid(idev, tmpaddr);
1316 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1317 	age = (now - ifp->tstamp) / HZ;
1318 
1319 	regen_advance = idev->cnf.regen_max_retry *
1320 			idev->cnf.dad_transmits *
1321 			NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
1322 
1323 	/* recalculate max_desync_factor each time and update
1324 	 * idev->desync_factor if it's larger
1325 	 */
1326 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1327 	max_desync_factor = min_t(__u32,
1328 				  idev->cnf.max_desync_factor,
1329 				  cnf_temp_preferred_lft - regen_advance);
1330 
1331 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1332 		if (max_desync_factor > 0) {
1333 			get_random_bytes(&idev->desync_factor,
1334 					 sizeof(idev->desync_factor));
1335 			idev->desync_factor %= max_desync_factor;
1336 		} else {
1337 			idev->desync_factor = 0;
1338 		}
1339 	}
1340 
1341 	tmp_valid_lft = min_t(__u32,
1342 			      ifp->valid_lft,
1343 			      idev->cnf.temp_valid_lft + age);
1344 	tmp_prefered_lft = cnf_temp_preferred_lft + age -
1345 			    idev->desync_factor;
1346 	tmp_prefered_lft = min_t(__u32, ifp->prefered_lft, tmp_prefered_lft);
1347 	tmp_plen = ifp->prefix_len;
1348 	tmp_tstamp = ifp->tstamp;
1349 	spin_unlock_bh(&ifp->lock);
1350 
1351 	write_unlock_bh(&idev->lock);
1352 
1353 	/* A temporary address is created only if this calculated Preferred
1354 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1355 	 * an implementation must not create a temporary address with a zero
1356 	 * Preferred Lifetime.
1357 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1358 	 * temporary addresses being generated.
1359 	 */
1360 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1361 	if (tmp_prefered_lft <= regen_advance + age) {
1362 		in6_ifa_put(ifp);
1363 		in6_dev_put(idev);
1364 		ret = -1;
1365 		goto out;
1366 	}
1367 
1368 	addr_flags = IFA_F_TEMPORARY;
1369 	/* set in addrconf_prefix_rcv() */
1370 	if (ifp->flags & IFA_F_OPTIMISTIC)
1371 		addr_flags |= IFA_F_OPTIMISTIC;
1372 
1373 	ift = ipv6_add_addr(idev, &addr, NULL, tmp_plen,
1374 			    ipv6_addr_scope(&addr), addr_flags,
1375 			    tmp_valid_lft, tmp_prefered_lft, true, NULL);
1376 	if (IS_ERR(ift)) {
1377 		in6_ifa_put(ifp);
1378 		in6_dev_put(idev);
1379 		pr_info("%s: retry temporary address regeneration\n", __func__);
1380 		tmpaddr = &addr;
1381 		write_lock_bh(&idev->lock);
1382 		goto retry;
1383 	}
1384 
1385 	spin_lock_bh(&ift->lock);
1386 	ift->ifpub = ifp;
1387 	ift->cstamp = now;
1388 	ift->tstamp = tmp_tstamp;
1389 	spin_unlock_bh(&ift->lock);
1390 
1391 	addrconf_dad_start(ift);
1392 	in6_ifa_put(ift);
1393 	in6_dev_put(idev);
1394 out:
1395 	return ret;
1396 }
1397 
1398 /*
1399  *	Choose an appropriate source address (RFC3484)
1400  */
1401 enum {
1402 	IPV6_SADDR_RULE_INIT = 0,
1403 	IPV6_SADDR_RULE_LOCAL,
1404 	IPV6_SADDR_RULE_SCOPE,
1405 	IPV6_SADDR_RULE_PREFERRED,
1406 #ifdef CONFIG_IPV6_MIP6
1407 	IPV6_SADDR_RULE_HOA,
1408 #endif
1409 	IPV6_SADDR_RULE_OIF,
1410 	IPV6_SADDR_RULE_LABEL,
1411 	IPV6_SADDR_RULE_PRIVACY,
1412 	IPV6_SADDR_RULE_ORCHID,
1413 	IPV6_SADDR_RULE_PREFIX,
1414 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1415 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1416 #endif
1417 	IPV6_SADDR_RULE_MAX
1418 };
1419 
1420 struct ipv6_saddr_score {
1421 	int			rule;
1422 	int			addr_type;
1423 	struct inet6_ifaddr	*ifa;
1424 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1425 	int			scopedist;
1426 	int			matchlen;
1427 };
1428 
1429 struct ipv6_saddr_dst {
1430 	const struct in6_addr *addr;
1431 	int ifindex;
1432 	int scope;
1433 	int label;
1434 	unsigned int prefs;
1435 };
1436 
1437 static inline int ipv6_saddr_preferred(int type)
1438 {
1439 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1440 		return 1;
1441 	return 0;
1442 }
1443 
1444 static bool ipv6_use_optimistic_addr(struct net *net,
1445 				     struct inet6_dev *idev)
1446 {
1447 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1448 	if (!idev)
1449 		return false;
1450 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1451 		return false;
1452 	if (!net->ipv6.devconf_all->use_optimistic && !idev->cnf.use_optimistic)
1453 		return false;
1454 
1455 	return true;
1456 #else
1457 	return false;
1458 #endif
1459 }
1460 
1461 static int ipv6_get_saddr_eval(struct net *net,
1462 			       struct ipv6_saddr_score *score,
1463 			       struct ipv6_saddr_dst *dst,
1464 			       int i)
1465 {
1466 	int ret;
1467 
1468 	if (i <= score->rule) {
1469 		switch (i) {
1470 		case IPV6_SADDR_RULE_SCOPE:
1471 			ret = score->scopedist;
1472 			break;
1473 		case IPV6_SADDR_RULE_PREFIX:
1474 			ret = score->matchlen;
1475 			break;
1476 		default:
1477 			ret = !!test_bit(i, score->scorebits);
1478 		}
1479 		goto out;
1480 	}
1481 
1482 	switch (i) {
1483 	case IPV6_SADDR_RULE_INIT:
1484 		/* Rule 0: remember if hiscore is not ready yet */
1485 		ret = !!score->ifa;
1486 		break;
1487 	case IPV6_SADDR_RULE_LOCAL:
1488 		/* Rule 1: Prefer same address */
1489 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1490 		break;
1491 	case IPV6_SADDR_RULE_SCOPE:
1492 		/* Rule 2: Prefer appropriate scope
1493 		 *
1494 		 *      ret
1495 		 *       ^
1496 		 *    -1 |  d 15
1497 		 *    ---+--+-+---> scope
1498 		 *       |
1499 		 *       |             d is scope of the destination.
1500 		 *  B-d  |  \
1501 		 *       |   \      <- smaller scope is better if
1502 		 *  B-15 |    \        if scope is enough for destination.
1503 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1504 		 * d-C-1 | /
1505 		 *       |/         <- greater is better
1506 		 *   -C  /             if scope is not enough for destination.
1507 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1508 		 *
1509 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1510 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1511 		 * Assume B = 0 and we get C > 29.
1512 		 */
1513 		ret = __ipv6_addr_src_scope(score->addr_type);
1514 		if (ret >= dst->scope)
1515 			ret = -ret;
1516 		else
1517 			ret -= 128;	/* 30 is enough */
1518 		score->scopedist = ret;
1519 		break;
1520 	case IPV6_SADDR_RULE_PREFERRED:
1521 	    {
1522 		/* Rule 3: Avoid deprecated and optimistic addresses */
1523 		u8 avoid = IFA_F_DEPRECATED;
1524 
1525 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1526 			avoid |= IFA_F_OPTIMISTIC;
1527 		ret = ipv6_saddr_preferred(score->addr_type) ||
1528 		      !(score->ifa->flags & avoid);
1529 		break;
1530 	    }
1531 #ifdef CONFIG_IPV6_MIP6
1532 	case IPV6_SADDR_RULE_HOA:
1533 	    {
1534 		/* Rule 4: Prefer home address */
1535 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1536 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1537 		break;
1538 	    }
1539 #endif
1540 	case IPV6_SADDR_RULE_OIF:
1541 		/* Rule 5: Prefer outgoing interface */
1542 		ret = (!dst->ifindex ||
1543 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1544 		break;
1545 	case IPV6_SADDR_RULE_LABEL:
1546 		/* Rule 6: Prefer matching label */
1547 		ret = ipv6_addr_label(net,
1548 				      &score->ifa->addr, score->addr_type,
1549 				      score->ifa->idev->dev->ifindex) == dst->label;
1550 		break;
1551 	case IPV6_SADDR_RULE_PRIVACY:
1552 	    {
1553 		/* Rule 7: Prefer public address
1554 		 * Note: prefer temporary address if use_tempaddr >= 2
1555 		 */
1556 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1557 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1558 				score->ifa->idev->cnf.use_tempaddr >= 2;
1559 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1560 		break;
1561 	    }
1562 	case IPV6_SADDR_RULE_ORCHID:
1563 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1564 		 *	    non-ORCHID vs non-ORCHID
1565 		 */
1566 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1567 			ipv6_addr_orchid(dst->addr));
1568 		break;
1569 	case IPV6_SADDR_RULE_PREFIX:
1570 		/* Rule 8: Use longest matching prefix */
1571 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1572 		if (ret > score->ifa->prefix_len)
1573 			ret = score->ifa->prefix_len;
1574 		score->matchlen = ret;
1575 		break;
1576 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1577 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1578 		/* Optimistic addresses still have lower precedence than other
1579 		 * preferred addresses.
1580 		 */
1581 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1582 		break;
1583 #endif
1584 	default:
1585 		ret = 0;
1586 	}
1587 
1588 	if (ret)
1589 		__set_bit(i, score->scorebits);
1590 	score->rule = i;
1591 out:
1592 	return ret;
1593 }
1594 
1595 static int __ipv6_dev_get_saddr(struct net *net,
1596 				struct ipv6_saddr_dst *dst,
1597 				struct inet6_dev *idev,
1598 				struct ipv6_saddr_score *scores,
1599 				int hiscore_idx)
1600 {
1601 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1602 
1603 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1604 		int i;
1605 
1606 		/*
1607 		 * - Tentative Address (RFC2462 section 5.4)
1608 		 *  - A tentative address is not considered
1609 		 *    "assigned to an interface" in the traditional
1610 		 *    sense, unless it is also flagged as optimistic.
1611 		 * - Candidate Source Address (section 4)
1612 		 *  - In any case, anycast addresses, multicast
1613 		 *    addresses, and the unspecified address MUST
1614 		 *    NOT be included in a candidate set.
1615 		 */
1616 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1617 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1618 			continue;
1619 
1620 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1621 
1622 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1623 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1624 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1625 					    idev->dev->name);
1626 			continue;
1627 		}
1628 
1629 		score->rule = -1;
1630 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1631 
1632 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1633 			int minihiscore, miniscore;
1634 
1635 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1636 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1637 
1638 			if (minihiscore > miniscore) {
1639 				if (i == IPV6_SADDR_RULE_SCOPE &&
1640 				    score->scopedist > 0) {
1641 					/*
1642 					 * special case:
1643 					 * each remaining entry
1644 					 * has too small (not enough)
1645 					 * scope, because ifa entries
1646 					 * are sorted by their scope
1647 					 * values.
1648 					 */
1649 					goto out;
1650 				}
1651 				break;
1652 			} else if (minihiscore < miniscore) {
1653 				swap(hiscore, score);
1654 				hiscore_idx = 1 - hiscore_idx;
1655 
1656 				/* restore our iterator */
1657 				score->ifa = hiscore->ifa;
1658 
1659 				break;
1660 			}
1661 		}
1662 	}
1663 out:
1664 	return hiscore_idx;
1665 }
1666 
1667 static int ipv6_get_saddr_master(struct net *net,
1668 				 const struct net_device *dst_dev,
1669 				 const struct net_device *master,
1670 				 struct ipv6_saddr_dst *dst,
1671 				 struct ipv6_saddr_score *scores,
1672 				 int hiscore_idx)
1673 {
1674 	struct inet6_dev *idev;
1675 
1676 	idev = __in6_dev_get(dst_dev);
1677 	if (idev)
1678 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1679 						   scores, hiscore_idx);
1680 
1681 	idev = __in6_dev_get(master);
1682 	if (idev)
1683 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1684 						   scores, hiscore_idx);
1685 
1686 	return hiscore_idx;
1687 }
1688 
1689 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1690 		       const struct in6_addr *daddr, unsigned int prefs,
1691 		       struct in6_addr *saddr)
1692 {
1693 	struct ipv6_saddr_score scores[2], *hiscore;
1694 	struct ipv6_saddr_dst dst;
1695 	struct inet6_dev *idev;
1696 	struct net_device *dev;
1697 	int dst_type;
1698 	bool use_oif_addr = false;
1699 	int hiscore_idx = 0;
1700 	int ret = 0;
1701 
1702 	dst_type = __ipv6_addr_type(daddr);
1703 	dst.addr = daddr;
1704 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1705 	dst.scope = __ipv6_addr_src_scope(dst_type);
1706 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1707 	dst.prefs = prefs;
1708 
1709 	scores[hiscore_idx].rule = -1;
1710 	scores[hiscore_idx].ifa = NULL;
1711 
1712 	rcu_read_lock();
1713 
1714 	/* Candidate Source Address (section 4)
1715 	 *  - multicast and link-local destination address,
1716 	 *    the set of candidate source address MUST only
1717 	 *    include addresses assigned to interfaces
1718 	 *    belonging to the same link as the outgoing
1719 	 *    interface.
1720 	 * (- For site-local destination addresses, the
1721 	 *    set of candidate source addresses MUST only
1722 	 *    include addresses assigned to interfaces
1723 	 *    belonging to the same site as the outgoing
1724 	 *    interface.)
1725 	 *  - "It is RECOMMENDED that the candidate source addresses
1726 	 *    be the set of unicast addresses assigned to the
1727 	 *    interface that will be used to send to the destination
1728 	 *    (the 'outgoing' interface)." (RFC 6724)
1729 	 */
1730 	if (dst_dev) {
1731 		idev = __in6_dev_get(dst_dev);
1732 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1733 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1734 		    (idev && idev->cnf.use_oif_addrs_only)) {
1735 			use_oif_addr = true;
1736 		}
1737 	}
1738 
1739 	if (use_oif_addr) {
1740 		if (idev)
1741 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1742 	} else {
1743 		const struct net_device *master;
1744 		int master_idx = 0;
1745 
1746 		/* if dst_dev exists and is enslaved to an L3 device, then
1747 		 * prefer addresses from dst_dev and then the master over
1748 		 * any other enslaved devices in the L3 domain.
1749 		 */
1750 		master = l3mdev_master_dev_rcu(dst_dev);
1751 		if (master) {
1752 			master_idx = master->ifindex;
1753 
1754 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1755 							    master, &dst,
1756 							    scores, hiscore_idx);
1757 
1758 			if (scores[hiscore_idx].ifa)
1759 				goto out;
1760 		}
1761 
1762 		for_each_netdev_rcu(net, dev) {
1763 			/* only consider addresses on devices in the
1764 			 * same L3 domain
1765 			 */
1766 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1767 				continue;
1768 			idev = __in6_dev_get(dev);
1769 			if (!idev)
1770 				continue;
1771 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1772 		}
1773 	}
1774 
1775 out:
1776 	hiscore = &scores[hiscore_idx];
1777 	if (!hiscore->ifa)
1778 		ret = -EADDRNOTAVAIL;
1779 	else
1780 		*saddr = hiscore->ifa->addr;
1781 
1782 	rcu_read_unlock();
1783 	return ret;
1784 }
1785 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1786 
1787 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1788 		      u32 banned_flags)
1789 {
1790 	struct inet6_ifaddr *ifp;
1791 	int err = -EADDRNOTAVAIL;
1792 
1793 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1794 		if (ifp->scope > IFA_LINK)
1795 			break;
1796 		if (ifp->scope == IFA_LINK &&
1797 		    !(ifp->flags & banned_flags)) {
1798 			*addr = ifp->addr;
1799 			err = 0;
1800 			break;
1801 		}
1802 	}
1803 	return err;
1804 }
1805 
1806 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1807 		    u32 banned_flags)
1808 {
1809 	struct inet6_dev *idev;
1810 	int err = -EADDRNOTAVAIL;
1811 
1812 	rcu_read_lock();
1813 	idev = __in6_dev_get(dev);
1814 	if (idev) {
1815 		read_lock_bh(&idev->lock);
1816 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1817 		read_unlock_bh(&idev->lock);
1818 	}
1819 	rcu_read_unlock();
1820 	return err;
1821 }
1822 
1823 static int ipv6_count_addresses(const struct inet6_dev *idev)
1824 {
1825 	const struct inet6_ifaddr *ifp;
1826 	int cnt = 0;
1827 
1828 	rcu_read_lock();
1829 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1830 		cnt++;
1831 	rcu_read_unlock();
1832 	return cnt;
1833 }
1834 
1835 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1836 		  const struct net_device *dev, int strict)
1837 {
1838 	return ipv6_chk_addr_and_flags(net, addr, dev, strict, IFA_F_TENTATIVE);
1839 }
1840 EXPORT_SYMBOL(ipv6_chk_addr);
1841 
1842 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1843 			    const struct net_device *dev, int strict,
1844 			    u32 banned_flags)
1845 {
1846 	struct inet6_ifaddr *ifp;
1847 	unsigned int hash = inet6_addr_hash(addr);
1848 	u32 ifp_flags;
1849 
1850 	rcu_read_lock_bh();
1851 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1852 		if (!net_eq(dev_net(ifp->idev->dev), net))
1853 			continue;
1854 		/* Decouple optimistic from tentative for evaluation here.
1855 		 * Ban optimistic addresses explicitly, when required.
1856 		 */
1857 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1858 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1859 			    : ifp->flags;
1860 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1861 		    !(ifp_flags&banned_flags) &&
1862 		    (!dev || ifp->idev->dev == dev ||
1863 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1864 			rcu_read_unlock_bh();
1865 			return 1;
1866 		}
1867 	}
1868 
1869 	rcu_read_unlock_bh();
1870 	return 0;
1871 }
1872 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1873 
1874 
1875 /* Compares an address/prefix_len with addresses on device @dev.
1876  * If one is found it returns true.
1877  */
1878 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1879 	const unsigned int prefix_len, struct net_device *dev)
1880 {
1881 	const struct inet6_ifaddr *ifa;
1882 	const struct inet6_dev *idev;
1883 	bool ret = false;
1884 
1885 	rcu_read_lock();
1886 	idev = __in6_dev_get(dev);
1887 	if (idev) {
1888 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1889 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1890 			if (ret)
1891 				break;
1892 		}
1893 	}
1894 	rcu_read_unlock();
1895 
1896 	return ret;
1897 }
1898 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1899 
1900 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1901 {
1902 	const struct inet6_ifaddr *ifa;
1903 	const struct inet6_dev *idev;
1904 	int	onlink;
1905 
1906 	onlink = 0;
1907 	rcu_read_lock();
1908 	idev = __in6_dev_get(dev);
1909 	if (idev) {
1910 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1911 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1912 						   ifa->prefix_len);
1913 			if (onlink)
1914 				break;
1915 		}
1916 	}
1917 	rcu_read_unlock();
1918 	return onlink;
1919 }
1920 EXPORT_SYMBOL(ipv6_chk_prefix);
1921 
1922 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1923 				     struct net_device *dev, int strict)
1924 {
1925 	struct inet6_ifaddr *ifp, *result = NULL;
1926 	unsigned int hash = inet6_addr_hash(addr);
1927 
1928 	rcu_read_lock_bh();
1929 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
1930 		if (!net_eq(dev_net(ifp->idev->dev), net))
1931 			continue;
1932 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1933 			if (!dev || ifp->idev->dev == dev ||
1934 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1935 				result = ifp;
1936 				in6_ifa_hold(ifp);
1937 				break;
1938 			}
1939 		}
1940 	}
1941 	rcu_read_unlock_bh();
1942 
1943 	return result;
1944 }
1945 
1946 /* Gets referenced address, destroys ifaddr */
1947 
1948 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1949 {
1950 	if (dad_failed)
1951 		ifp->flags |= IFA_F_DADFAILED;
1952 
1953 	if (ifp->flags&IFA_F_TEMPORARY) {
1954 		struct inet6_ifaddr *ifpub;
1955 		spin_lock_bh(&ifp->lock);
1956 		ifpub = ifp->ifpub;
1957 		if (ifpub) {
1958 			in6_ifa_hold(ifpub);
1959 			spin_unlock_bh(&ifp->lock);
1960 			ipv6_create_tempaddr(ifpub, ifp);
1961 			in6_ifa_put(ifpub);
1962 		} else {
1963 			spin_unlock_bh(&ifp->lock);
1964 		}
1965 		ipv6_del_addr(ifp);
1966 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
1967 		spin_lock_bh(&ifp->lock);
1968 		addrconf_del_dad_work(ifp);
1969 		ifp->flags |= IFA_F_TENTATIVE;
1970 		spin_unlock_bh(&ifp->lock);
1971 		if (dad_failed)
1972 			ipv6_ifa_notify(0, ifp);
1973 		in6_ifa_put(ifp);
1974 	} else {
1975 		ipv6_del_addr(ifp);
1976 	}
1977 }
1978 
1979 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1980 {
1981 	int err = -ENOENT;
1982 
1983 	spin_lock_bh(&ifp->lock);
1984 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
1985 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
1986 		err = 0;
1987 	}
1988 	spin_unlock_bh(&ifp->lock);
1989 
1990 	return err;
1991 }
1992 
1993 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1994 {
1995 	struct inet6_dev *idev = ifp->idev;
1996 	struct net *net = dev_net(ifp->idev->dev);
1997 
1998 	if (addrconf_dad_end(ifp)) {
1999 		in6_ifa_put(ifp);
2000 		return;
2001 	}
2002 
2003 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c detected!\n",
2004 			     ifp->idev->dev->name, &ifp->addr);
2005 
2006 	spin_lock_bh(&ifp->lock);
2007 
2008 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2009 		int scope = ifp->scope;
2010 		u32 flags = ifp->flags;
2011 		struct in6_addr new_addr;
2012 		struct inet6_ifaddr *ifp2;
2013 		u32 valid_lft, preferred_lft;
2014 		int pfxlen = ifp->prefix_len;
2015 		int retries = ifp->stable_privacy_retry + 1;
2016 
2017 		if (retries > net->ipv6.sysctl.idgen_retries) {
2018 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2019 					     ifp->idev->dev->name);
2020 			goto errdad;
2021 		}
2022 
2023 		new_addr = ifp->addr;
2024 		if (ipv6_generate_stable_address(&new_addr, retries,
2025 						 idev))
2026 			goto errdad;
2027 
2028 		valid_lft = ifp->valid_lft;
2029 		preferred_lft = ifp->prefered_lft;
2030 
2031 		spin_unlock_bh(&ifp->lock);
2032 
2033 		if (idev->cnf.max_addresses &&
2034 		    ipv6_count_addresses(idev) >=
2035 		    idev->cnf.max_addresses)
2036 			goto lock_errdad;
2037 
2038 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2039 				     ifp->idev->dev->name);
2040 
2041 		ifp2 = ipv6_add_addr(idev, &new_addr, NULL, pfxlen,
2042 				     scope, flags, valid_lft,
2043 				     preferred_lft, false, NULL);
2044 		if (IS_ERR(ifp2))
2045 			goto lock_errdad;
2046 
2047 		spin_lock_bh(&ifp2->lock);
2048 		ifp2->stable_privacy_retry = retries;
2049 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2050 		spin_unlock_bh(&ifp2->lock);
2051 
2052 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2053 		in6_ifa_put(ifp2);
2054 lock_errdad:
2055 		spin_lock_bh(&ifp->lock);
2056 	}
2057 
2058 errdad:
2059 	/* transition from _POSTDAD to _ERRDAD */
2060 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2061 	spin_unlock_bh(&ifp->lock);
2062 
2063 	addrconf_mod_dad_work(ifp, 0);
2064 	in6_ifa_put(ifp);
2065 }
2066 
2067 /* Join to solicited addr multicast group.
2068  * caller must hold RTNL */
2069 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2070 {
2071 	struct in6_addr maddr;
2072 
2073 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2074 		return;
2075 
2076 	addrconf_addr_solict_mult(addr, &maddr);
2077 	ipv6_dev_mc_inc(dev, &maddr);
2078 }
2079 
2080 /* caller must hold RTNL */
2081 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2082 {
2083 	struct in6_addr maddr;
2084 
2085 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2086 		return;
2087 
2088 	addrconf_addr_solict_mult(addr, &maddr);
2089 	__ipv6_dev_mc_dec(idev, &maddr);
2090 }
2091 
2092 /* caller must hold RTNL */
2093 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2094 {
2095 	struct in6_addr addr;
2096 
2097 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2098 		return;
2099 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2100 	if (ipv6_addr_any(&addr))
2101 		return;
2102 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2103 }
2104 
2105 /* caller must hold RTNL */
2106 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2107 {
2108 	struct in6_addr addr;
2109 
2110 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2111 		return;
2112 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2113 	if (ipv6_addr_any(&addr))
2114 		return;
2115 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2116 }
2117 
2118 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2119 {
2120 	switch (dev->addr_len) {
2121 	case ETH_ALEN:
2122 		memcpy(eui, dev->dev_addr, 3);
2123 		eui[3] = 0xFF;
2124 		eui[4] = 0xFE;
2125 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2126 		break;
2127 	case EUI64_ADDR_LEN:
2128 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2129 		eui[0] ^= 2;
2130 		break;
2131 	default:
2132 		return -1;
2133 	}
2134 
2135 	return 0;
2136 }
2137 
2138 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2139 {
2140 	union fwnet_hwaddr *ha;
2141 
2142 	if (dev->addr_len != FWNET_ALEN)
2143 		return -1;
2144 
2145 	ha = (union fwnet_hwaddr *)dev->dev_addr;
2146 
2147 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2148 	eui[0] ^= 2;
2149 	return 0;
2150 }
2151 
2152 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2153 {
2154 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2155 	if (dev->addr_len != ARCNET_ALEN)
2156 		return -1;
2157 	memset(eui, 0, 7);
2158 	eui[7] = *(u8 *)dev->dev_addr;
2159 	return 0;
2160 }
2161 
2162 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2163 {
2164 	if (dev->addr_len != INFINIBAND_ALEN)
2165 		return -1;
2166 	memcpy(eui, dev->dev_addr + 12, 8);
2167 	eui[0] |= 2;
2168 	return 0;
2169 }
2170 
2171 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2172 {
2173 	if (addr == 0)
2174 		return -1;
2175 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2176 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2177 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2178 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2179 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2180 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2181 	eui[1] = 0;
2182 	eui[2] = 0x5E;
2183 	eui[3] = 0xFE;
2184 	memcpy(eui + 4, &addr, 4);
2185 	return 0;
2186 }
2187 
2188 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2189 {
2190 	if (dev->priv_flags & IFF_ISATAP)
2191 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2192 	return -1;
2193 }
2194 
2195 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2196 {
2197 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2198 }
2199 
2200 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2201 {
2202 	memcpy(eui, dev->perm_addr, 3);
2203 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2204 	eui[3] = 0xFF;
2205 	eui[4] = 0xFE;
2206 	eui[0] ^= 2;
2207 	return 0;
2208 }
2209 
2210 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2211 {
2212 	switch (dev->type) {
2213 	case ARPHRD_ETHER:
2214 	case ARPHRD_FDDI:
2215 		return addrconf_ifid_eui48(eui, dev);
2216 	case ARPHRD_ARCNET:
2217 		return addrconf_ifid_arcnet(eui, dev);
2218 	case ARPHRD_INFINIBAND:
2219 		return addrconf_ifid_infiniband(eui, dev);
2220 	case ARPHRD_SIT:
2221 		return addrconf_ifid_sit(eui, dev);
2222 	case ARPHRD_IPGRE:
2223 	case ARPHRD_TUNNEL:
2224 		return addrconf_ifid_gre(eui, dev);
2225 	case ARPHRD_6LOWPAN:
2226 		return addrconf_ifid_6lowpan(eui, dev);
2227 	case ARPHRD_IEEE1394:
2228 		return addrconf_ifid_ieee1394(eui, dev);
2229 	case ARPHRD_TUNNEL6:
2230 	case ARPHRD_IP6GRE:
2231 		return addrconf_ifid_ip6tnl(eui, dev);
2232 	}
2233 	return -1;
2234 }
2235 
2236 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2237 {
2238 	int err = -1;
2239 	struct inet6_ifaddr *ifp;
2240 
2241 	read_lock_bh(&idev->lock);
2242 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2243 		if (ifp->scope > IFA_LINK)
2244 			break;
2245 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2246 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2247 			err = 0;
2248 			break;
2249 		}
2250 	}
2251 	read_unlock_bh(&idev->lock);
2252 	return err;
2253 }
2254 
2255 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
2256 static void ipv6_regen_rndid(struct inet6_dev *idev)
2257 {
2258 regen:
2259 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
2260 	idev->rndid[0] &= ~0x02;
2261 
2262 	/*
2263 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
2264 	 * check if generated address is not inappropriate
2265 	 *
2266 	 *  - Reserved subnet anycast (RFC 2526)
2267 	 *	11111101 11....11 1xxxxxxx
2268 	 *  - ISATAP (RFC4214) 6.1
2269 	 *	00-00-5E-FE-xx-xx-xx-xx
2270 	 *  - value 0
2271 	 *  - XXX: already assigned to an address on the device
2272 	 */
2273 	if (idev->rndid[0] == 0xfd &&
2274 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
2275 	    (idev->rndid[7]&0x80))
2276 		goto regen;
2277 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
2278 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
2279 			goto regen;
2280 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
2281 			goto regen;
2282 	}
2283 }
2284 
2285 static void  ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
2286 {
2287 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
2288 		ipv6_regen_rndid(idev);
2289 }
2290 
2291 /*
2292  *	Add prefix route.
2293  */
2294 
2295 static void
2296 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
2297 		      unsigned long expires, u32 flags)
2298 {
2299 	struct fib6_config cfg = {
2300 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2301 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2302 		.fc_ifindex = dev->ifindex,
2303 		.fc_expires = expires,
2304 		.fc_dst_len = plen,
2305 		.fc_flags = RTF_UP | flags,
2306 		.fc_nlinfo.nl_net = dev_net(dev),
2307 		.fc_protocol = RTPROT_KERNEL,
2308 	};
2309 
2310 	cfg.fc_dst = *pfx;
2311 
2312 	/* Prevent useless cloning on PtP SIT.
2313 	   This thing is done here expecting that the whole
2314 	   class of non-broadcast devices need not cloning.
2315 	 */
2316 #if IS_ENABLED(CONFIG_IPV6_SIT)
2317 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2318 		cfg.fc_flags |= RTF_NONEXTHOP;
2319 #endif
2320 
2321 	ip6_route_add(&cfg, NULL);
2322 }
2323 
2324 
2325 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2326 						  int plen,
2327 						  const struct net_device *dev,
2328 						  u32 flags, u32 noflags)
2329 {
2330 	struct fib6_node *fn;
2331 	struct rt6_info *rt = NULL;
2332 	struct fib6_table *table;
2333 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2334 
2335 	table = fib6_get_table(dev_net(dev), tb_id);
2336 	if (!table)
2337 		return NULL;
2338 
2339 	rcu_read_lock();
2340 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2341 	if (!fn)
2342 		goto out;
2343 
2344 	for_each_fib6_node_rt_rcu(fn) {
2345 		if (rt->dst.dev->ifindex != dev->ifindex)
2346 			continue;
2347 		if ((rt->rt6i_flags & flags) != flags)
2348 			continue;
2349 		if ((rt->rt6i_flags & noflags) != 0)
2350 			continue;
2351 		if (!dst_hold_safe(&rt->dst))
2352 			rt = NULL;
2353 		break;
2354 	}
2355 out:
2356 	rcu_read_unlock();
2357 	return rt;
2358 }
2359 
2360 
2361 /* Create "default" multicast route to the interface */
2362 
2363 static void addrconf_add_mroute(struct net_device *dev)
2364 {
2365 	struct fib6_config cfg = {
2366 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2367 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2368 		.fc_ifindex = dev->ifindex,
2369 		.fc_dst_len = 8,
2370 		.fc_flags = RTF_UP,
2371 		.fc_nlinfo.nl_net = dev_net(dev),
2372 	};
2373 
2374 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2375 
2376 	ip6_route_add(&cfg, NULL);
2377 }
2378 
2379 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2380 {
2381 	struct inet6_dev *idev;
2382 
2383 	ASSERT_RTNL();
2384 
2385 	idev = ipv6_find_idev(dev);
2386 	if (!idev)
2387 		return ERR_PTR(-ENOBUFS);
2388 
2389 	if (idev->cnf.disable_ipv6)
2390 		return ERR_PTR(-EACCES);
2391 
2392 	/* Add default multicast route */
2393 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2394 		addrconf_add_mroute(dev);
2395 
2396 	return idev;
2397 }
2398 
2399 static void manage_tempaddrs(struct inet6_dev *idev,
2400 			     struct inet6_ifaddr *ifp,
2401 			     __u32 valid_lft, __u32 prefered_lft,
2402 			     bool create, unsigned long now)
2403 {
2404 	u32 flags;
2405 	struct inet6_ifaddr *ift;
2406 
2407 	read_lock_bh(&idev->lock);
2408 	/* update all temporary addresses in the list */
2409 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2410 		int age, max_valid, max_prefered;
2411 
2412 		if (ifp != ift->ifpub)
2413 			continue;
2414 
2415 		/* RFC 4941 section 3.3:
2416 		 * If a received option will extend the lifetime of a public
2417 		 * address, the lifetimes of temporary addresses should
2418 		 * be extended, subject to the overall constraint that no
2419 		 * temporary addresses should ever remain "valid" or "preferred"
2420 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2421 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2422 		 */
2423 		age = (now - ift->cstamp) / HZ;
2424 		max_valid = idev->cnf.temp_valid_lft - age;
2425 		if (max_valid < 0)
2426 			max_valid = 0;
2427 
2428 		max_prefered = idev->cnf.temp_prefered_lft -
2429 			       idev->desync_factor - age;
2430 		if (max_prefered < 0)
2431 			max_prefered = 0;
2432 
2433 		if (valid_lft > max_valid)
2434 			valid_lft = max_valid;
2435 
2436 		if (prefered_lft > max_prefered)
2437 			prefered_lft = max_prefered;
2438 
2439 		spin_lock(&ift->lock);
2440 		flags = ift->flags;
2441 		ift->valid_lft = valid_lft;
2442 		ift->prefered_lft = prefered_lft;
2443 		ift->tstamp = now;
2444 		if (prefered_lft > 0)
2445 			ift->flags &= ~IFA_F_DEPRECATED;
2446 
2447 		spin_unlock(&ift->lock);
2448 		if (!(flags&IFA_F_TENTATIVE))
2449 			ipv6_ifa_notify(0, ift);
2450 	}
2451 
2452 	if ((create || list_empty(&idev->tempaddr_list)) &&
2453 	    idev->cnf.use_tempaddr > 0) {
2454 		/* When a new public address is created as described
2455 		 * in [ADDRCONF], also create a new temporary address.
2456 		 * Also create a temporary address if it's enabled but
2457 		 * no temporary address currently exists.
2458 		 */
2459 		read_unlock_bh(&idev->lock);
2460 		ipv6_create_tempaddr(ifp, NULL);
2461 	} else {
2462 		read_unlock_bh(&idev->lock);
2463 	}
2464 }
2465 
2466 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2467 {
2468 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2469 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2470 }
2471 
2472 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2473 				 const struct prefix_info *pinfo,
2474 				 struct inet6_dev *in6_dev,
2475 				 const struct in6_addr *addr, int addr_type,
2476 				 u32 addr_flags, bool sllao, bool tokenized,
2477 				 __u32 valid_lft, u32 prefered_lft)
2478 {
2479 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2480 	int create = 0, update_lft = 0;
2481 
2482 	if (!ifp && valid_lft) {
2483 		int max_addresses = in6_dev->cnf.max_addresses;
2484 
2485 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2486 		if ((net->ipv6.devconf_all->optimistic_dad ||
2487 		     in6_dev->cnf.optimistic_dad) &&
2488 		    !net->ipv6.devconf_all->forwarding && sllao)
2489 			addr_flags |= IFA_F_OPTIMISTIC;
2490 #endif
2491 
2492 		/* Do not allow to create too much of autoconfigured
2493 		 * addresses; this would be too easy way to crash kernel.
2494 		 */
2495 		if (!max_addresses ||
2496 		    ipv6_count_addresses(in6_dev) < max_addresses)
2497 			ifp = ipv6_add_addr(in6_dev, addr, NULL,
2498 					    pinfo->prefix_len,
2499 					    addr_type&IPV6_ADDR_SCOPE_MASK,
2500 					    addr_flags, valid_lft,
2501 					    prefered_lft, false, NULL);
2502 
2503 		if (IS_ERR_OR_NULL(ifp))
2504 			return -1;
2505 
2506 		update_lft = 0;
2507 		create = 1;
2508 		spin_lock_bh(&ifp->lock);
2509 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2510 		ifp->cstamp = jiffies;
2511 		ifp->tokenized = tokenized;
2512 		spin_unlock_bh(&ifp->lock);
2513 		addrconf_dad_start(ifp);
2514 	}
2515 
2516 	if (ifp) {
2517 		u32 flags;
2518 		unsigned long now;
2519 		u32 stored_lft;
2520 
2521 		/* update lifetime (RFC2462 5.5.3 e) */
2522 		spin_lock_bh(&ifp->lock);
2523 		now = jiffies;
2524 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2525 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2526 		else
2527 			stored_lft = 0;
2528 		if (!update_lft && !create && stored_lft) {
2529 			const u32 minimum_lft = min_t(u32,
2530 				stored_lft, MIN_VALID_LIFETIME);
2531 			valid_lft = max(valid_lft, minimum_lft);
2532 
2533 			/* RFC4862 Section 5.5.3e:
2534 			 * "Note that the preferred lifetime of the
2535 			 *  corresponding address is always reset to
2536 			 *  the Preferred Lifetime in the received
2537 			 *  Prefix Information option, regardless of
2538 			 *  whether the valid lifetime is also reset or
2539 			 *  ignored."
2540 			 *
2541 			 * So we should always update prefered_lft here.
2542 			 */
2543 			update_lft = 1;
2544 		}
2545 
2546 		if (update_lft) {
2547 			ifp->valid_lft = valid_lft;
2548 			ifp->prefered_lft = prefered_lft;
2549 			ifp->tstamp = now;
2550 			flags = ifp->flags;
2551 			ifp->flags &= ~IFA_F_DEPRECATED;
2552 			spin_unlock_bh(&ifp->lock);
2553 
2554 			if (!(flags&IFA_F_TENTATIVE))
2555 				ipv6_ifa_notify(0, ifp);
2556 		} else
2557 			spin_unlock_bh(&ifp->lock);
2558 
2559 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2560 				 create, now);
2561 
2562 		in6_ifa_put(ifp);
2563 		addrconf_verify();
2564 	}
2565 
2566 	return 0;
2567 }
2568 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2569 
2570 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2571 {
2572 	struct prefix_info *pinfo;
2573 	__u32 valid_lft;
2574 	__u32 prefered_lft;
2575 	int addr_type, err;
2576 	u32 addr_flags = 0;
2577 	struct inet6_dev *in6_dev;
2578 	struct net *net = dev_net(dev);
2579 
2580 	pinfo = (struct prefix_info *) opt;
2581 
2582 	if (len < sizeof(struct prefix_info)) {
2583 		ADBG("addrconf: prefix option too short\n");
2584 		return;
2585 	}
2586 
2587 	/*
2588 	 *	Validation checks ([ADDRCONF], page 19)
2589 	 */
2590 
2591 	addr_type = ipv6_addr_type(&pinfo->prefix);
2592 
2593 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2594 		return;
2595 
2596 	valid_lft = ntohl(pinfo->valid);
2597 	prefered_lft = ntohl(pinfo->prefered);
2598 
2599 	if (prefered_lft > valid_lft) {
2600 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2601 		return;
2602 	}
2603 
2604 	in6_dev = in6_dev_get(dev);
2605 
2606 	if (!in6_dev) {
2607 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2608 				    dev->name);
2609 		return;
2610 	}
2611 
2612 	/*
2613 	 *	Two things going on here:
2614 	 *	1) Add routes for on-link prefixes
2615 	 *	2) Configure prefixes with the auto flag set
2616 	 */
2617 
2618 	if (pinfo->onlink) {
2619 		struct rt6_info *rt;
2620 		unsigned long rt_expires;
2621 
2622 		/* Avoid arithmetic overflow. Really, we could
2623 		 * save rt_expires in seconds, likely valid_lft,
2624 		 * but it would require division in fib gc, that it
2625 		 * not good.
2626 		 */
2627 		if (HZ > USER_HZ)
2628 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2629 		else
2630 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2631 
2632 		if (addrconf_finite_timeout(rt_expires))
2633 			rt_expires *= HZ;
2634 
2635 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2636 					       pinfo->prefix_len,
2637 					       dev,
2638 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2639 					       RTF_GATEWAY | RTF_DEFAULT);
2640 
2641 		if (rt) {
2642 			/* Autoconf prefix route */
2643 			if (valid_lft == 0) {
2644 				ip6_del_rt(rt);
2645 				rt = NULL;
2646 			} else if (addrconf_finite_timeout(rt_expires)) {
2647 				/* not infinity */
2648 				rt6_set_expires(rt, jiffies + rt_expires);
2649 			} else {
2650 				rt6_clean_expires(rt);
2651 			}
2652 		} else if (valid_lft) {
2653 			clock_t expires = 0;
2654 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2655 			if (addrconf_finite_timeout(rt_expires)) {
2656 				/* not infinity */
2657 				flags |= RTF_EXPIRES;
2658 				expires = jiffies_to_clock_t(rt_expires);
2659 			}
2660 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2661 					      dev, expires, flags);
2662 		}
2663 		ip6_rt_put(rt);
2664 	}
2665 
2666 	/* Try to figure out our local address for this prefix */
2667 
2668 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2669 		struct in6_addr addr;
2670 		bool tokenized = false, dev_addr_generated = false;
2671 
2672 		if (pinfo->prefix_len == 64) {
2673 			memcpy(&addr, &pinfo->prefix, 8);
2674 
2675 			if (!ipv6_addr_any(&in6_dev->token)) {
2676 				read_lock_bh(&in6_dev->lock);
2677 				memcpy(addr.s6_addr + 8,
2678 				       in6_dev->token.s6_addr + 8, 8);
2679 				read_unlock_bh(&in6_dev->lock);
2680 				tokenized = true;
2681 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2682 				   !ipv6_generate_stable_address(&addr, 0,
2683 								 in6_dev)) {
2684 				addr_flags |= IFA_F_STABLE_PRIVACY;
2685 				goto ok;
2686 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2687 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2688 				goto put;
2689 			} else {
2690 				dev_addr_generated = true;
2691 			}
2692 			goto ok;
2693 		}
2694 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2695 				    pinfo->prefix_len);
2696 		goto put;
2697 
2698 ok:
2699 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2700 						   &addr, addr_type,
2701 						   addr_flags, sllao,
2702 						   tokenized, valid_lft,
2703 						   prefered_lft);
2704 		if (err)
2705 			goto put;
2706 
2707 		/* Ignore error case here because previous prefix add addr was
2708 		 * successful which will be notified.
2709 		 */
2710 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2711 					      addr_type, addr_flags, sllao,
2712 					      tokenized, valid_lft,
2713 					      prefered_lft,
2714 					      dev_addr_generated);
2715 	}
2716 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2717 put:
2718 	in6_dev_put(in6_dev);
2719 }
2720 
2721 /*
2722  *	Set destination address.
2723  *	Special case for SIT interfaces where we create a new "virtual"
2724  *	device.
2725  */
2726 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2727 {
2728 	struct in6_ifreq ireq;
2729 	struct net_device *dev;
2730 	int err = -EINVAL;
2731 
2732 	rtnl_lock();
2733 
2734 	err = -EFAULT;
2735 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2736 		goto err_exit;
2737 
2738 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2739 
2740 	err = -ENODEV;
2741 	if (!dev)
2742 		goto err_exit;
2743 
2744 #if IS_ENABLED(CONFIG_IPV6_SIT)
2745 	if (dev->type == ARPHRD_SIT) {
2746 		const struct net_device_ops *ops = dev->netdev_ops;
2747 		struct ifreq ifr;
2748 		struct ip_tunnel_parm p;
2749 
2750 		err = -EADDRNOTAVAIL;
2751 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2752 			goto err_exit;
2753 
2754 		memset(&p, 0, sizeof(p));
2755 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2756 		p.iph.saddr = 0;
2757 		p.iph.version = 4;
2758 		p.iph.ihl = 5;
2759 		p.iph.protocol = IPPROTO_IPV6;
2760 		p.iph.ttl = 64;
2761 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2762 
2763 		if (ops->ndo_do_ioctl) {
2764 			mm_segment_t oldfs = get_fs();
2765 
2766 			set_fs(KERNEL_DS);
2767 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2768 			set_fs(oldfs);
2769 		} else
2770 			err = -EOPNOTSUPP;
2771 
2772 		if (err == 0) {
2773 			err = -ENOBUFS;
2774 			dev = __dev_get_by_name(net, p.name);
2775 			if (!dev)
2776 				goto err_exit;
2777 			err = dev_open(dev);
2778 		}
2779 	}
2780 #endif
2781 
2782 err_exit:
2783 	rtnl_unlock();
2784 	return err;
2785 }
2786 
2787 static int ipv6_mc_config(struct sock *sk, bool join,
2788 			  const struct in6_addr *addr, int ifindex)
2789 {
2790 	int ret;
2791 
2792 	ASSERT_RTNL();
2793 
2794 	lock_sock(sk);
2795 	if (join)
2796 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2797 	else
2798 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2799 	release_sock(sk);
2800 
2801 	return ret;
2802 }
2803 
2804 /*
2805  *	Manual configuration of address on an interface
2806  */
2807 static int inet6_addr_add(struct net *net, int ifindex,
2808 			  const struct in6_addr *pfx,
2809 			  const struct in6_addr *peer_pfx,
2810 			  unsigned int plen, __u32 ifa_flags,
2811 			  __u32 prefered_lft, __u32 valid_lft,
2812 			  struct netlink_ext_ack *extack)
2813 {
2814 	struct inet6_ifaddr *ifp;
2815 	struct inet6_dev *idev;
2816 	struct net_device *dev;
2817 	unsigned long timeout;
2818 	clock_t expires;
2819 	int scope;
2820 	u32 flags;
2821 
2822 	ASSERT_RTNL();
2823 
2824 	if (plen > 128)
2825 		return -EINVAL;
2826 
2827 	/* check the lifetime */
2828 	if (!valid_lft || prefered_lft > valid_lft)
2829 		return -EINVAL;
2830 
2831 	if (ifa_flags & IFA_F_MANAGETEMPADDR && plen != 64)
2832 		return -EINVAL;
2833 
2834 	dev = __dev_get_by_index(net, ifindex);
2835 	if (!dev)
2836 		return -ENODEV;
2837 
2838 	idev = addrconf_add_dev(dev);
2839 	if (IS_ERR(idev))
2840 		return PTR_ERR(idev);
2841 
2842 	if (ifa_flags & IFA_F_MCAUTOJOIN) {
2843 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2844 					 true, pfx, ifindex);
2845 
2846 		if (ret < 0)
2847 			return ret;
2848 	}
2849 
2850 	scope = ipv6_addr_scope(pfx);
2851 
2852 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
2853 	if (addrconf_finite_timeout(timeout)) {
2854 		expires = jiffies_to_clock_t(timeout * HZ);
2855 		valid_lft = timeout;
2856 		flags = RTF_EXPIRES;
2857 	} else {
2858 		expires = 0;
2859 		flags = 0;
2860 		ifa_flags |= IFA_F_PERMANENT;
2861 	}
2862 
2863 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2864 	if (addrconf_finite_timeout(timeout)) {
2865 		if (timeout == 0)
2866 			ifa_flags |= IFA_F_DEPRECATED;
2867 		prefered_lft = timeout;
2868 	}
2869 
2870 	ifp = ipv6_add_addr(idev, pfx, peer_pfx, plen, scope, ifa_flags,
2871 			    valid_lft, prefered_lft, true, extack);
2872 
2873 	if (!IS_ERR(ifp)) {
2874 		if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
2875 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2876 					      expires, flags);
2877 		}
2878 
2879 		/*
2880 		 * Note that section 3.1 of RFC 4429 indicates
2881 		 * that the Optimistic flag should not be set for
2882 		 * manually configured addresses
2883 		 */
2884 		addrconf_dad_start(ifp);
2885 		if (ifa_flags & IFA_F_MANAGETEMPADDR)
2886 			manage_tempaddrs(idev, ifp, valid_lft, prefered_lft,
2887 					 true, jiffies);
2888 		in6_ifa_put(ifp);
2889 		addrconf_verify_rtnl();
2890 		return 0;
2891 	} else if (ifa_flags & IFA_F_MCAUTOJOIN) {
2892 		ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2893 			       false, pfx, ifindex);
2894 	}
2895 
2896 	return PTR_ERR(ifp);
2897 }
2898 
2899 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2900 			  const struct in6_addr *pfx, unsigned int plen)
2901 {
2902 	struct inet6_ifaddr *ifp;
2903 	struct inet6_dev *idev;
2904 	struct net_device *dev;
2905 
2906 	if (plen > 128)
2907 		return -EINVAL;
2908 
2909 	dev = __dev_get_by_index(net, ifindex);
2910 	if (!dev)
2911 		return -ENODEV;
2912 
2913 	idev = __in6_dev_get(dev);
2914 	if (!idev)
2915 		return -ENXIO;
2916 
2917 	read_lock_bh(&idev->lock);
2918 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2919 		if (ifp->prefix_len == plen &&
2920 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2921 			in6_ifa_hold(ifp);
2922 			read_unlock_bh(&idev->lock);
2923 
2924 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
2925 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
2926 				manage_tempaddrs(idev, ifp, 0, 0, false,
2927 						 jiffies);
2928 			ipv6_del_addr(ifp);
2929 			addrconf_verify_rtnl();
2930 			if (ipv6_addr_is_multicast(pfx)) {
2931 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2932 					       false, pfx, dev->ifindex);
2933 			}
2934 			return 0;
2935 		}
2936 	}
2937 	read_unlock_bh(&idev->lock);
2938 	return -EADDRNOTAVAIL;
2939 }
2940 
2941 
2942 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2943 {
2944 	struct in6_ifreq ireq;
2945 	int err;
2946 
2947 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2948 		return -EPERM;
2949 
2950 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2951 		return -EFAULT;
2952 
2953 	rtnl_lock();
2954 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr, NULL,
2955 			     ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2956 			     INFINITY_LIFE_TIME, INFINITY_LIFE_TIME, NULL);
2957 	rtnl_unlock();
2958 	return err;
2959 }
2960 
2961 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2962 {
2963 	struct in6_ifreq ireq;
2964 	int err;
2965 
2966 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2967 		return -EPERM;
2968 
2969 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2970 		return -EFAULT;
2971 
2972 	rtnl_lock();
2973 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
2974 			     ireq.ifr6_prefixlen);
2975 	rtnl_unlock();
2976 	return err;
2977 }
2978 
2979 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
2980 		     int plen, int scope)
2981 {
2982 	struct inet6_ifaddr *ifp;
2983 
2984 	ifp = ipv6_add_addr(idev, addr, NULL, plen,
2985 			    scope, IFA_F_PERMANENT,
2986 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME,
2987 			    true, NULL);
2988 	if (!IS_ERR(ifp)) {
2989 		spin_lock_bh(&ifp->lock);
2990 		ifp->flags &= ~IFA_F_TENTATIVE;
2991 		spin_unlock_bh(&ifp->lock);
2992 		rt_genid_bump_ipv6(dev_net(idev->dev));
2993 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
2994 		in6_ifa_put(ifp);
2995 	}
2996 }
2997 
2998 #if IS_ENABLED(CONFIG_IPV6_SIT)
2999 static void sit_add_v4_addrs(struct inet6_dev *idev)
3000 {
3001 	struct in6_addr addr;
3002 	struct net_device *dev;
3003 	struct net *net = dev_net(idev->dev);
3004 	int scope, plen;
3005 	u32 pflags = 0;
3006 
3007 	ASSERT_RTNL();
3008 
3009 	memset(&addr, 0, sizeof(struct in6_addr));
3010 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3011 
3012 	if (idev->dev->flags&IFF_POINTOPOINT) {
3013 		addr.s6_addr32[0] = htonl(0xfe800000);
3014 		scope = IFA_LINK;
3015 		plen = 64;
3016 	} else {
3017 		scope = IPV6_ADDR_COMPATv4;
3018 		plen = 96;
3019 		pflags |= RTF_NONEXTHOP;
3020 	}
3021 
3022 	if (addr.s6_addr32[3]) {
3023 		add_addr(idev, &addr, plen, scope);
3024 		addrconf_prefix_route(&addr, plen, idev->dev, 0, pflags);
3025 		return;
3026 	}
3027 
3028 	for_each_netdev(net, dev) {
3029 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3030 		if (in_dev && (dev->flags & IFF_UP)) {
3031 			struct in_ifaddr *ifa;
3032 
3033 			int flag = scope;
3034 
3035 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
3036 
3037 				addr.s6_addr32[3] = ifa->ifa_local;
3038 
3039 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3040 					continue;
3041 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3042 					if (idev->dev->flags&IFF_POINTOPOINT)
3043 						continue;
3044 					flag |= IFA_HOST;
3045 				}
3046 
3047 				add_addr(idev, &addr, plen, flag);
3048 				addrconf_prefix_route(&addr, plen, idev->dev, 0,
3049 						      pflags);
3050 			}
3051 		}
3052 	}
3053 }
3054 #endif
3055 
3056 static void init_loopback(struct net_device *dev)
3057 {
3058 	struct inet6_dev  *idev;
3059 
3060 	/* ::1 */
3061 
3062 	ASSERT_RTNL();
3063 
3064 	idev = ipv6_find_idev(dev);
3065 	if (!idev) {
3066 		pr_debug("%s: add_dev failed\n", __func__);
3067 		return;
3068 	}
3069 
3070 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
3071 }
3072 
3073 void addrconf_add_linklocal(struct inet6_dev *idev,
3074 			    const struct in6_addr *addr, u32 flags)
3075 {
3076 	struct inet6_ifaddr *ifp;
3077 	u32 addr_flags = flags | IFA_F_PERMANENT;
3078 
3079 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3080 	if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3081 	     idev->cnf.optimistic_dad) &&
3082 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3083 		addr_flags |= IFA_F_OPTIMISTIC;
3084 #endif
3085 
3086 	ifp = ipv6_add_addr(idev, addr, NULL, 64, IFA_LINK, addr_flags,
3087 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME, true, NULL);
3088 	if (!IS_ERR(ifp)) {
3089 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
3090 		addrconf_dad_start(ifp);
3091 		in6_ifa_put(ifp);
3092 	}
3093 }
3094 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3095 
3096 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3097 {
3098 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3099 		return true;
3100 
3101 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3102 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3103 		return true;
3104 
3105 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3106 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3107 		return true;
3108 
3109 	return false;
3110 }
3111 
3112 static int ipv6_generate_stable_address(struct in6_addr *address,
3113 					u8 dad_count,
3114 					const struct inet6_dev *idev)
3115 {
3116 	static DEFINE_SPINLOCK(lock);
3117 	static __u32 digest[SHA_DIGEST_WORDS];
3118 	static __u32 workspace[SHA_WORKSPACE_WORDS];
3119 
3120 	static union {
3121 		char __data[SHA_MESSAGE_BYTES];
3122 		struct {
3123 			struct in6_addr secret;
3124 			__be32 prefix[2];
3125 			unsigned char hwaddr[MAX_ADDR_LEN];
3126 			u8 dad_count;
3127 		} __packed;
3128 	} data;
3129 
3130 	struct in6_addr secret;
3131 	struct in6_addr temp;
3132 	struct net *net = dev_net(idev->dev);
3133 
3134 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3135 
3136 	if (idev->cnf.stable_secret.initialized)
3137 		secret = idev->cnf.stable_secret.secret;
3138 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3139 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3140 	else
3141 		return -1;
3142 
3143 retry:
3144 	spin_lock_bh(&lock);
3145 
3146 	sha_init(digest);
3147 	memset(&data, 0, sizeof(data));
3148 	memset(workspace, 0, sizeof(workspace));
3149 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3150 	data.prefix[0] = address->s6_addr32[0];
3151 	data.prefix[1] = address->s6_addr32[1];
3152 	data.secret = secret;
3153 	data.dad_count = dad_count;
3154 
3155 	sha_transform(digest, data.__data, workspace);
3156 
3157 	temp = *address;
3158 	temp.s6_addr32[2] = (__force __be32)digest[0];
3159 	temp.s6_addr32[3] = (__force __be32)digest[1];
3160 
3161 	spin_unlock_bh(&lock);
3162 
3163 	if (ipv6_reserved_interfaceid(temp)) {
3164 		dad_count++;
3165 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3166 			return -1;
3167 		goto retry;
3168 	}
3169 
3170 	*address = temp;
3171 	return 0;
3172 }
3173 
3174 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3175 {
3176 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3177 
3178 	if (s->initialized)
3179 		return;
3180 	s = &idev->cnf.stable_secret;
3181 	get_random_bytes(&s->secret, sizeof(s->secret));
3182 	s->initialized = true;
3183 }
3184 
3185 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3186 {
3187 	struct in6_addr addr;
3188 
3189 	/* no link local addresses on L3 master devices */
3190 	if (netif_is_l3_master(idev->dev))
3191 		return;
3192 
3193 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3194 
3195 	switch (idev->cnf.addr_gen_mode) {
3196 	case IN6_ADDR_GEN_MODE_RANDOM:
3197 		ipv6_gen_mode_random_init(idev);
3198 		/* fallthrough */
3199 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3200 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3201 			addrconf_add_linklocal(idev, &addr,
3202 					       IFA_F_STABLE_PRIVACY);
3203 		else if (prefix_route)
3204 			addrconf_prefix_route(&addr, 64, idev->dev, 0, 0);
3205 		break;
3206 	case IN6_ADDR_GEN_MODE_EUI64:
3207 		/* addrconf_add_linklocal also adds a prefix_route and we
3208 		 * only need to care about prefix routes if ipv6_generate_eui64
3209 		 * couldn't generate one.
3210 		 */
3211 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3212 			addrconf_add_linklocal(idev, &addr, 0);
3213 		else if (prefix_route)
3214 			addrconf_prefix_route(&addr, 64, idev->dev, 0, 0);
3215 		break;
3216 	case IN6_ADDR_GEN_MODE_NONE:
3217 	default:
3218 		/* will not add any link local address */
3219 		break;
3220 	}
3221 }
3222 
3223 static void addrconf_dev_config(struct net_device *dev)
3224 {
3225 	struct inet6_dev *idev;
3226 
3227 	ASSERT_RTNL();
3228 
3229 	if ((dev->type != ARPHRD_ETHER) &&
3230 	    (dev->type != ARPHRD_FDDI) &&
3231 	    (dev->type != ARPHRD_ARCNET) &&
3232 	    (dev->type != ARPHRD_INFINIBAND) &&
3233 	    (dev->type != ARPHRD_IEEE1394) &&
3234 	    (dev->type != ARPHRD_TUNNEL6) &&
3235 	    (dev->type != ARPHRD_6LOWPAN) &&
3236 	    (dev->type != ARPHRD_IP6GRE) &&
3237 	    (dev->type != ARPHRD_IPGRE) &&
3238 	    (dev->type != ARPHRD_TUNNEL) &&
3239 	    (dev->type != ARPHRD_NONE)) {
3240 		/* Alas, we support only Ethernet autoconfiguration. */
3241 		return;
3242 	}
3243 
3244 	idev = addrconf_add_dev(dev);
3245 	if (IS_ERR(idev))
3246 		return;
3247 
3248 	/* this device type has no EUI support */
3249 	if (dev->type == ARPHRD_NONE &&
3250 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3251 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3252 
3253 	addrconf_addr_gen(idev, false);
3254 }
3255 
3256 #if IS_ENABLED(CONFIG_IPV6_SIT)
3257 static void addrconf_sit_config(struct net_device *dev)
3258 {
3259 	struct inet6_dev *idev;
3260 
3261 	ASSERT_RTNL();
3262 
3263 	/*
3264 	 * Configure the tunnel with one of our IPv4
3265 	 * addresses... we should configure all of
3266 	 * our v4 addrs in the tunnel
3267 	 */
3268 
3269 	idev = ipv6_find_idev(dev);
3270 	if (!idev) {
3271 		pr_debug("%s: add_dev failed\n", __func__);
3272 		return;
3273 	}
3274 
3275 	if (dev->priv_flags & IFF_ISATAP) {
3276 		addrconf_addr_gen(idev, false);
3277 		return;
3278 	}
3279 
3280 	sit_add_v4_addrs(idev);
3281 
3282 	if (dev->flags&IFF_POINTOPOINT)
3283 		addrconf_add_mroute(dev);
3284 }
3285 #endif
3286 
3287 #if IS_ENABLED(CONFIG_NET_IPGRE)
3288 static void addrconf_gre_config(struct net_device *dev)
3289 {
3290 	struct inet6_dev *idev;
3291 
3292 	ASSERT_RTNL();
3293 
3294 	idev = ipv6_find_idev(dev);
3295 	if (!idev) {
3296 		pr_debug("%s: add_dev failed\n", __func__);
3297 		return;
3298 	}
3299 
3300 	addrconf_addr_gen(idev, true);
3301 	if (dev->flags & IFF_POINTOPOINT)
3302 		addrconf_add_mroute(dev);
3303 }
3304 #endif
3305 
3306 static int fixup_permanent_addr(struct inet6_dev *idev,
3307 				struct inet6_ifaddr *ifp)
3308 {
3309 	/* !rt6i_node means the host route was removed from the
3310 	 * FIB, for example, if 'lo' device is taken down. In that
3311 	 * case regenerate the host route.
3312 	 */
3313 	if (!ifp->rt || !ifp->rt->rt6i_node) {
3314 		struct rt6_info *rt, *prev;
3315 
3316 		rt = addrconf_dst_alloc(idev, &ifp->addr, false);
3317 		if (IS_ERR(rt))
3318 			return PTR_ERR(rt);
3319 
3320 		/* ifp->rt can be accessed outside of rtnl */
3321 		spin_lock(&ifp->lock);
3322 		prev = ifp->rt;
3323 		ifp->rt = rt;
3324 		spin_unlock(&ifp->lock);
3325 
3326 		ip6_rt_put(prev);
3327 	}
3328 
3329 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3330 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3331 				      idev->dev, 0, 0);
3332 	}
3333 
3334 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3335 		addrconf_dad_start(ifp);
3336 
3337 	return 0;
3338 }
3339 
3340 static void addrconf_permanent_addr(struct net_device *dev)
3341 {
3342 	struct inet6_ifaddr *ifp, *tmp;
3343 	struct inet6_dev *idev;
3344 
3345 	idev = __in6_dev_get(dev);
3346 	if (!idev)
3347 		return;
3348 
3349 	write_lock_bh(&idev->lock);
3350 
3351 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3352 		if ((ifp->flags & IFA_F_PERMANENT) &&
3353 		    fixup_permanent_addr(idev, ifp) < 0) {
3354 			write_unlock_bh(&idev->lock);
3355 			ipv6_del_addr(ifp);
3356 			write_lock_bh(&idev->lock);
3357 
3358 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3359 					     idev->dev->name, &ifp->addr);
3360 		}
3361 	}
3362 
3363 	write_unlock_bh(&idev->lock);
3364 }
3365 
3366 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3367 			   void *ptr)
3368 {
3369 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3370 	struct netdev_notifier_changeupper_info *info;
3371 	struct inet6_dev *idev = __in6_dev_get(dev);
3372 	struct net *net = dev_net(dev);
3373 	int run_pending = 0;
3374 	int err;
3375 
3376 	switch (event) {
3377 	case NETDEV_REGISTER:
3378 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3379 			idev = ipv6_add_dev(dev);
3380 			if (IS_ERR(idev))
3381 				return notifier_from_errno(PTR_ERR(idev));
3382 		}
3383 		break;
3384 
3385 	case NETDEV_CHANGEMTU:
3386 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3387 		if (dev->mtu < IPV6_MIN_MTU) {
3388 			addrconf_ifdown(dev, dev != net->loopback_dev);
3389 			break;
3390 		}
3391 
3392 		if (idev) {
3393 			rt6_mtu_change(dev, dev->mtu);
3394 			idev->cnf.mtu6 = dev->mtu;
3395 			break;
3396 		}
3397 
3398 		/* allocate new idev */
3399 		idev = ipv6_add_dev(dev);
3400 		if (IS_ERR(idev))
3401 			break;
3402 
3403 		/* device is still not ready */
3404 		if (!(idev->if_flags & IF_READY))
3405 			break;
3406 
3407 		run_pending = 1;
3408 
3409 		/* fall through */
3410 
3411 	case NETDEV_UP:
3412 	case NETDEV_CHANGE:
3413 		if (dev->flags & IFF_SLAVE)
3414 			break;
3415 
3416 		if (idev && idev->cnf.disable_ipv6)
3417 			break;
3418 
3419 		if (event == NETDEV_UP) {
3420 			/* restore routes for permanent addresses */
3421 			addrconf_permanent_addr(dev);
3422 
3423 			if (!addrconf_link_ready(dev)) {
3424 				/* device is not ready yet. */
3425 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3426 					dev->name);
3427 				break;
3428 			}
3429 
3430 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3431 				idev = ipv6_add_dev(dev);
3432 
3433 			if (!IS_ERR_OR_NULL(idev)) {
3434 				idev->if_flags |= IF_READY;
3435 				run_pending = 1;
3436 			}
3437 		} else if (event == NETDEV_CHANGE) {
3438 			if (!addrconf_link_ready(dev)) {
3439 				/* device is still not ready. */
3440 				break;
3441 			}
3442 
3443 			if (idev) {
3444 				if (idev->if_flags & IF_READY) {
3445 					/* device is already configured -
3446 					 * but resend MLD reports, we might
3447 					 * have roamed and need to update
3448 					 * multicast snooping switches
3449 					 */
3450 					ipv6_mc_up(idev);
3451 					break;
3452 				}
3453 				idev->if_flags |= IF_READY;
3454 			}
3455 
3456 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3457 				dev->name);
3458 
3459 			run_pending = 1;
3460 		}
3461 
3462 		switch (dev->type) {
3463 #if IS_ENABLED(CONFIG_IPV6_SIT)
3464 		case ARPHRD_SIT:
3465 			addrconf_sit_config(dev);
3466 			break;
3467 #endif
3468 #if IS_ENABLED(CONFIG_NET_IPGRE)
3469 		case ARPHRD_IPGRE:
3470 			addrconf_gre_config(dev);
3471 			break;
3472 #endif
3473 		case ARPHRD_LOOPBACK:
3474 			init_loopback(dev);
3475 			break;
3476 
3477 		default:
3478 			addrconf_dev_config(dev);
3479 			break;
3480 		}
3481 
3482 		if (!IS_ERR_OR_NULL(idev)) {
3483 			if (run_pending)
3484 				addrconf_dad_run(idev);
3485 
3486 			/*
3487 			 * If the MTU changed during the interface down,
3488 			 * when the interface up, the changed MTU must be
3489 			 * reflected in the idev as well as routers.
3490 			 */
3491 			if (idev->cnf.mtu6 != dev->mtu &&
3492 			    dev->mtu >= IPV6_MIN_MTU) {
3493 				rt6_mtu_change(dev, dev->mtu);
3494 				idev->cnf.mtu6 = dev->mtu;
3495 			}
3496 			idev->tstamp = jiffies;
3497 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3498 
3499 			/*
3500 			 * If the changed mtu during down is lower than
3501 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3502 			 */
3503 			if (dev->mtu < IPV6_MIN_MTU)
3504 				addrconf_ifdown(dev, dev != net->loopback_dev);
3505 		}
3506 		break;
3507 
3508 	case NETDEV_DOWN:
3509 	case NETDEV_UNREGISTER:
3510 		/*
3511 		 *	Remove all addresses from this interface.
3512 		 */
3513 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3514 		break;
3515 
3516 	case NETDEV_CHANGENAME:
3517 		if (idev) {
3518 			snmp6_unregister_dev(idev);
3519 			addrconf_sysctl_unregister(idev);
3520 			err = addrconf_sysctl_register(idev);
3521 			if (err)
3522 				return notifier_from_errno(err);
3523 			err = snmp6_register_dev(idev);
3524 			if (err) {
3525 				addrconf_sysctl_unregister(idev);
3526 				return notifier_from_errno(err);
3527 			}
3528 		}
3529 		break;
3530 
3531 	case NETDEV_PRE_TYPE_CHANGE:
3532 	case NETDEV_POST_TYPE_CHANGE:
3533 		if (idev)
3534 			addrconf_type_change(dev, event);
3535 		break;
3536 
3537 	case NETDEV_CHANGEUPPER:
3538 		info = ptr;
3539 
3540 		/* flush all routes if dev is linked to or unlinked from
3541 		 * an L3 master device (e.g., VRF)
3542 		 */
3543 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3544 			addrconf_ifdown(dev, 0);
3545 	}
3546 
3547 	return NOTIFY_OK;
3548 }
3549 
3550 /*
3551  *	addrconf module should be notified of a device going up
3552  */
3553 static struct notifier_block ipv6_dev_notf = {
3554 	.notifier_call = addrconf_notify,
3555 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3556 };
3557 
3558 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3559 {
3560 	struct inet6_dev *idev;
3561 	ASSERT_RTNL();
3562 
3563 	idev = __in6_dev_get(dev);
3564 
3565 	if (event == NETDEV_POST_TYPE_CHANGE)
3566 		ipv6_mc_remap(idev);
3567 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3568 		ipv6_mc_unmap(idev);
3569 }
3570 
3571 static bool addr_is_local(const struct in6_addr *addr)
3572 {
3573 	return ipv6_addr_type(addr) &
3574 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3575 }
3576 
3577 static int addrconf_ifdown(struct net_device *dev, int how)
3578 {
3579 	struct net *net = dev_net(dev);
3580 	struct inet6_dev *idev;
3581 	struct inet6_ifaddr *ifa, *tmp;
3582 	int _keep_addr;
3583 	bool keep_addr;
3584 	int state, i;
3585 
3586 	ASSERT_RTNL();
3587 
3588 	rt6_ifdown(net, dev);
3589 	neigh_ifdown(&nd_tbl, dev);
3590 
3591 	idev = __in6_dev_get(dev);
3592 	if (!idev)
3593 		return -ENODEV;
3594 
3595 	/*
3596 	 * Step 1: remove reference to ipv6 device from parent device.
3597 	 *	   Do not dev_put!
3598 	 */
3599 	if (how) {
3600 		idev->dead = 1;
3601 
3602 		/* protected by rtnl_lock */
3603 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3604 
3605 		/* Step 1.5: remove snmp6 entry */
3606 		snmp6_unregister_dev(idev);
3607 
3608 	}
3609 
3610 	/* aggregate the system setting and interface setting */
3611 	_keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3612 	if (!_keep_addr)
3613 		_keep_addr = idev->cnf.keep_addr_on_down;
3614 
3615 	/* combine the user config with event to determine if permanent
3616 	 * addresses are to be removed from address hash table
3617 	 */
3618 	keep_addr = !(how || _keep_addr <= 0 || idev->cnf.disable_ipv6);
3619 
3620 	/* Step 2: clear hash table */
3621 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3622 		struct hlist_head *h = &inet6_addr_lst[i];
3623 
3624 		spin_lock_bh(&addrconf_hash_lock);
3625 restart:
3626 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3627 			if (ifa->idev == idev) {
3628 				addrconf_del_dad_work(ifa);
3629 				/* combined flag + permanent flag decide if
3630 				 * address is retained on a down event
3631 				 */
3632 				if (!keep_addr ||
3633 				    !(ifa->flags & IFA_F_PERMANENT) ||
3634 				    addr_is_local(&ifa->addr)) {
3635 					hlist_del_init_rcu(&ifa->addr_lst);
3636 					goto restart;
3637 				}
3638 			}
3639 		}
3640 		spin_unlock_bh(&addrconf_hash_lock);
3641 	}
3642 
3643 	write_lock_bh(&idev->lock);
3644 
3645 	addrconf_del_rs_timer(idev);
3646 
3647 	/* Step 2: clear flags for stateless addrconf */
3648 	if (!how)
3649 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3650 
3651 	/* Step 3: clear tempaddr list */
3652 	while (!list_empty(&idev->tempaddr_list)) {
3653 		ifa = list_first_entry(&idev->tempaddr_list,
3654 				       struct inet6_ifaddr, tmp_list);
3655 		list_del(&ifa->tmp_list);
3656 		write_unlock_bh(&idev->lock);
3657 		spin_lock_bh(&ifa->lock);
3658 
3659 		if (ifa->ifpub) {
3660 			in6_ifa_put(ifa->ifpub);
3661 			ifa->ifpub = NULL;
3662 		}
3663 		spin_unlock_bh(&ifa->lock);
3664 		in6_ifa_put(ifa);
3665 		write_lock_bh(&idev->lock);
3666 	}
3667 
3668 	/* re-combine the user config with event to determine if permanent
3669 	 * addresses are to be removed from the interface list
3670 	 */
3671 	keep_addr = (!how && _keep_addr > 0 && !idev->cnf.disable_ipv6);
3672 
3673 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3674 		struct rt6_info *rt = NULL;
3675 		bool keep;
3676 
3677 		addrconf_del_dad_work(ifa);
3678 
3679 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3680 			!addr_is_local(&ifa->addr);
3681 
3682 		write_unlock_bh(&idev->lock);
3683 		spin_lock_bh(&ifa->lock);
3684 
3685 		if (keep) {
3686 			/* set state to skip the notifier below */
3687 			state = INET6_IFADDR_STATE_DEAD;
3688 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3689 			if (!(ifa->flags & IFA_F_NODAD))
3690 				ifa->flags |= IFA_F_TENTATIVE;
3691 
3692 			rt = ifa->rt;
3693 			ifa->rt = NULL;
3694 		} else {
3695 			state = ifa->state;
3696 			ifa->state = INET6_IFADDR_STATE_DEAD;
3697 		}
3698 
3699 		spin_unlock_bh(&ifa->lock);
3700 
3701 		if (rt)
3702 			ip6_del_rt(rt);
3703 
3704 		if (state != INET6_IFADDR_STATE_DEAD) {
3705 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3706 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3707 		} else {
3708 			if (idev->cnf.forwarding)
3709 				addrconf_leave_anycast(ifa);
3710 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3711 		}
3712 
3713 		write_lock_bh(&idev->lock);
3714 		if (!keep) {
3715 			list_del_rcu(&ifa->if_list);
3716 			in6_ifa_put(ifa);
3717 		}
3718 	}
3719 
3720 	write_unlock_bh(&idev->lock);
3721 
3722 	/* Step 5: Discard anycast and multicast list */
3723 	if (how) {
3724 		ipv6_ac_destroy_dev(idev);
3725 		ipv6_mc_destroy_dev(idev);
3726 	} else {
3727 		ipv6_mc_down(idev);
3728 	}
3729 
3730 	idev->tstamp = jiffies;
3731 
3732 	/* Last: Shot the device (if unregistered) */
3733 	if (how) {
3734 		addrconf_sysctl_unregister(idev);
3735 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3736 		neigh_ifdown(&nd_tbl, dev);
3737 		in6_dev_put(idev);
3738 	}
3739 	return 0;
3740 }
3741 
3742 static void addrconf_rs_timer(unsigned long data)
3743 {
3744 	struct inet6_dev *idev = (struct inet6_dev *)data;
3745 	struct net_device *dev = idev->dev;
3746 	struct in6_addr lladdr;
3747 
3748 	write_lock(&idev->lock);
3749 	if (idev->dead || !(idev->if_flags & IF_READY))
3750 		goto out;
3751 
3752 	if (!ipv6_accept_ra(idev))
3753 		goto out;
3754 
3755 	/* Announcement received after solicitation was sent */
3756 	if (idev->if_flags & IF_RA_RCVD)
3757 		goto out;
3758 
3759 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3760 		write_unlock(&idev->lock);
3761 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3762 			ndisc_send_rs(dev, &lladdr,
3763 				      &in6addr_linklocal_allrouters);
3764 		else
3765 			goto put;
3766 
3767 		write_lock(&idev->lock);
3768 		idev->rs_interval = rfc3315_s14_backoff_update(
3769 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3770 		/* The wait after the last probe can be shorter */
3771 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3772 					     idev->cnf.rtr_solicits) ?
3773 				      idev->cnf.rtr_solicit_delay :
3774 				      idev->rs_interval);
3775 	} else {
3776 		/*
3777 		 * Note: we do not support deprecated "all on-link"
3778 		 * assumption any longer.
3779 		 */
3780 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3781 	}
3782 
3783 out:
3784 	write_unlock(&idev->lock);
3785 put:
3786 	in6_dev_put(idev);
3787 }
3788 
3789 /*
3790  *	Duplicate Address Detection
3791  */
3792 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3793 {
3794 	unsigned long rand_num;
3795 	struct inet6_dev *idev = ifp->idev;
3796 	u64 nonce;
3797 
3798 	if (ifp->flags & IFA_F_OPTIMISTIC)
3799 		rand_num = 0;
3800 	else
3801 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3802 
3803 	nonce = 0;
3804 	if (idev->cnf.enhanced_dad ||
3805 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
3806 		do
3807 			get_random_bytes(&nonce, 6);
3808 		while (nonce == 0);
3809 	}
3810 	ifp->dad_nonce = nonce;
3811 	ifp->dad_probes = idev->cnf.dad_transmits;
3812 	addrconf_mod_dad_work(ifp, rand_num);
3813 }
3814 
3815 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3816 {
3817 	struct inet6_dev *idev = ifp->idev;
3818 	struct net_device *dev = idev->dev;
3819 	bool bump_id, notify = false;
3820 
3821 	addrconf_join_solict(dev, &ifp->addr);
3822 
3823 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3824 
3825 	read_lock_bh(&idev->lock);
3826 	spin_lock(&ifp->lock);
3827 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3828 		goto out;
3829 
3830 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3831 	    (dev_net(dev)->ipv6.devconf_all->accept_dad < 1 &&
3832 	     idev->cnf.accept_dad < 1) ||
3833 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3834 	    ifp->flags & IFA_F_NODAD) {
3835 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3836 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3837 		spin_unlock(&ifp->lock);
3838 		read_unlock_bh(&idev->lock);
3839 
3840 		addrconf_dad_completed(ifp, bump_id);
3841 		return;
3842 	}
3843 
3844 	if (!(idev->if_flags & IF_READY)) {
3845 		spin_unlock(&ifp->lock);
3846 		read_unlock_bh(&idev->lock);
3847 		/*
3848 		 * If the device is not ready:
3849 		 * - keep it tentative if it is a permanent address.
3850 		 * - otherwise, kill it.
3851 		 */
3852 		in6_ifa_hold(ifp);
3853 		addrconf_dad_stop(ifp, 0);
3854 		return;
3855 	}
3856 
3857 	/*
3858 	 * Optimistic nodes can start receiving
3859 	 * Frames right away
3860 	 */
3861 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3862 		ip6_ins_rt(ifp->rt);
3863 		if (ipv6_use_optimistic_addr(dev_net(dev), idev)) {
3864 			/* Because optimistic nodes can use this address,
3865 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3866 			 */
3867 			notify = true;
3868 		}
3869 	}
3870 
3871 	addrconf_dad_kick(ifp);
3872 out:
3873 	spin_unlock(&ifp->lock);
3874 	read_unlock_bh(&idev->lock);
3875 	if (notify)
3876 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3877 }
3878 
3879 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3880 {
3881 	bool begin_dad = false;
3882 
3883 	spin_lock_bh(&ifp->lock);
3884 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
3885 		ifp->state = INET6_IFADDR_STATE_PREDAD;
3886 		begin_dad = true;
3887 	}
3888 	spin_unlock_bh(&ifp->lock);
3889 
3890 	if (begin_dad)
3891 		addrconf_mod_dad_work(ifp, 0);
3892 }
3893 
3894 static void addrconf_dad_work(struct work_struct *w)
3895 {
3896 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
3897 						struct inet6_ifaddr,
3898 						dad_work);
3899 	struct inet6_dev *idev = ifp->idev;
3900 	bool bump_id, disable_ipv6 = false;
3901 	struct in6_addr mcaddr;
3902 
3903 	enum {
3904 		DAD_PROCESS,
3905 		DAD_BEGIN,
3906 		DAD_ABORT,
3907 	} action = DAD_PROCESS;
3908 
3909 	rtnl_lock();
3910 
3911 	spin_lock_bh(&ifp->lock);
3912 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
3913 		action = DAD_BEGIN;
3914 		ifp->state = INET6_IFADDR_STATE_DAD;
3915 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
3916 		action = DAD_ABORT;
3917 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
3918 
3919 		if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
3920 		     idev->cnf.accept_dad > 1) &&
3921 		    !idev->cnf.disable_ipv6 &&
3922 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
3923 			struct in6_addr addr;
3924 
3925 			addr.s6_addr32[0] = htonl(0xfe800000);
3926 			addr.s6_addr32[1] = 0;
3927 
3928 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
3929 			    ipv6_addr_equal(&ifp->addr, &addr)) {
3930 				/* DAD failed for link-local based on MAC */
3931 				idev->cnf.disable_ipv6 = 1;
3932 
3933 				pr_info("%s: IPv6 being disabled!\n",
3934 					ifp->idev->dev->name);
3935 				disable_ipv6 = true;
3936 			}
3937 		}
3938 	}
3939 	spin_unlock_bh(&ifp->lock);
3940 
3941 	if (action == DAD_BEGIN) {
3942 		addrconf_dad_begin(ifp);
3943 		goto out;
3944 	} else if (action == DAD_ABORT) {
3945 		in6_ifa_hold(ifp);
3946 		addrconf_dad_stop(ifp, 1);
3947 		if (disable_ipv6)
3948 			addrconf_ifdown(idev->dev, 0);
3949 		goto out;
3950 	}
3951 
3952 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
3953 		goto out;
3954 
3955 	write_lock_bh(&idev->lock);
3956 	if (idev->dead || !(idev->if_flags & IF_READY)) {
3957 		write_unlock_bh(&idev->lock);
3958 		goto out;
3959 	}
3960 
3961 	spin_lock(&ifp->lock);
3962 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
3963 		spin_unlock(&ifp->lock);
3964 		write_unlock_bh(&idev->lock);
3965 		goto out;
3966 	}
3967 
3968 	if (ifp->dad_probes == 0) {
3969 		/*
3970 		 * DAD was successful
3971 		 */
3972 
3973 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3974 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3975 		spin_unlock(&ifp->lock);
3976 		write_unlock_bh(&idev->lock);
3977 
3978 		addrconf_dad_completed(ifp, bump_id);
3979 
3980 		goto out;
3981 	}
3982 
3983 	ifp->dad_probes--;
3984 	addrconf_mod_dad_work(ifp,
3985 			      NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
3986 	spin_unlock(&ifp->lock);
3987 	write_unlock_bh(&idev->lock);
3988 
3989 	/* send a neighbour solicitation for our addr */
3990 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
3991 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
3992 		      ifp->dad_nonce);
3993 out:
3994 	in6_ifa_put(ifp);
3995 	rtnl_unlock();
3996 }
3997 
3998 /* ifp->idev must be at least read locked */
3999 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4000 {
4001 	struct inet6_ifaddr *ifpiter;
4002 	struct inet6_dev *idev = ifp->idev;
4003 
4004 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4005 		if (ifpiter->scope > IFA_LINK)
4006 			break;
4007 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4008 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4009 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4010 		    IFA_F_PERMANENT)
4011 			return false;
4012 	}
4013 	return true;
4014 }
4015 
4016 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id)
4017 {
4018 	struct net_device *dev = ifp->idev->dev;
4019 	struct in6_addr lladdr;
4020 	bool send_rs, send_mld;
4021 
4022 	addrconf_del_dad_work(ifp);
4023 
4024 	/*
4025 	 *	Configure the address for reception. Now it is valid.
4026 	 */
4027 
4028 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4029 
4030 	/* If added prefix is link local and we are prepared to process
4031 	   router advertisements, start sending router solicitations.
4032 	 */
4033 
4034 	read_lock_bh(&ifp->idev->lock);
4035 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4036 	send_rs = send_mld &&
4037 		  ipv6_accept_ra(ifp->idev) &&
4038 		  ifp->idev->cnf.rtr_solicits != 0 &&
4039 		  (dev->flags&IFF_LOOPBACK) == 0;
4040 	read_unlock_bh(&ifp->idev->lock);
4041 
4042 	/* While dad is in progress mld report's source address is in6_addrany.
4043 	 * Resend with proper ll now.
4044 	 */
4045 	if (send_mld)
4046 		ipv6_mc_dad_complete(ifp->idev);
4047 
4048 	if (send_rs) {
4049 		/*
4050 		 *	If a host as already performed a random delay
4051 		 *	[...] as part of DAD [...] there is no need
4052 		 *	to delay again before sending the first RS
4053 		 */
4054 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4055 			return;
4056 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4057 
4058 		write_lock_bh(&ifp->idev->lock);
4059 		spin_lock(&ifp->lock);
4060 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4061 			ifp->idev->cnf.rtr_solicit_interval);
4062 		ifp->idev->rs_probes = 1;
4063 		ifp->idev->if_flags |= IF_RS_SENT;
4064 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4065 		spin_unlock(&ifp->lock);
4066 		write_unlock_bh(&ifp->idev->lock);
4067 	}
4068 
4069 	if (bump_id)
4070 		rt_genid_bump_ipv6(dev_net(dev));
4071 
4072 	/* Make sure that a new temporary address will be created
4073 	 * before this temporary address becomes deprecated.
4074 	 */
4075 	if (ifp->flags & IFA_F_TEMPORARY)
4076 		addrconf_verify_rtnl();
4077 }
4078 
4079 static void addrconf_dad_run(struct inet6_dev *idev)
4080 {
4081 	struct inet6_ifaddr *ifp;
4082 
4083 	read_lock_bh(&idev->lock);
4084 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4085 		spin_lock(&ifp->lock);
4086 		if (ifp->flags & IFA_F_TENTATIVE &&
4087 		    ifp->state == INET6_IFADDR_STATE_DAD)
4088 			addrconf_dad_kick(ifp);
4089 		spin_unlock(&ifp->lock);
4090 	}
4091 	read_unlock_bh(&idev->lock);
4092 }
4093 
4094 #ifdef CONFIG_PROC_FS
4095 struct if6_iter_state {
4096 	struct seq_net_private p;
4097 	int bucket;
4098 	int offset;
4099 };
4100 
4101 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4102 {
4103 	struct inet6_ifaddr *ifa = NULL;
4104 	struct if6_iter_state *state = seq->private;
4105 	struct net *net = seq_file_net(seq);
4106 	int p = 0;
4107 
4108 	/* initial bucket if pos is 0 */
4109 	if (pos == 0) {
4110 		state->bucket = 0;
4111 		state->offset = 0;
4112 	}
4113 
4114 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4115 		hlist_for_each_entry_rcu_bh(ifa, &inet6_addr_lst[state->bucket],
4116 					 addr_lst) {
4117 			if (!net_eq(dev_net(ifa->idev->dev), net))
4118 				continue;
4119 			/* sync with offset */
4120 			if (p < state->offset) {
4121 				p++;
4122 				continue;
4123 			}
4124 			state->offset++;
4125 			return ifa;
4126 		}
4127 
4128 		/* prepare for next bucket */
4129 		state->offset = 0;
4130 		p = 0;
4131 	}
4132 	return NULL;
4133 }
4134 
4135 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4136 					 struct inet6_ifaddr *ifa)
4137 {
4138 	struct if6_iter_state *state = seq->private;
4139 	struct net *net = seq_file_net(seq);
4140 
4141 	hlist_for_each_entry_continue_rcu_bh(ifa, addr_lst) {
4142 		if (!net_eq(dev_net(ifa->idev->dev), net))
4143 			continue;
4144 		state->offset++;
4145 		return ifa;
4146 	}
4147 
4148 	while (++state->bucket < IN6_ADDR_HSIZE) {
4149 		state->offset = 0;
4150 		hlist_for_each_entry_rcu_bh(ifa,
4151 				     &inet6_addr_lst[state->bucket], addr_lst) {
4152 			if (!net_eq(dev_net(ifa->idev->dev), net))
4153 				continue;
4154 			state->offset++;
4155 			return ifa;
4156 		}
4157 	}
4158 
4159 	return NULL;
4160 }
4161 
4162 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4163 	__acquires(rcu_bh)
4164 {
4165 	rcu_read_lock_bh();
4166 	return if6_get_first(seq, *pos);
4167 }
4168 
4169 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4170 {
4171 	struct inet6_ifaddr *ifa;
4172 
4173 	ifa = if6_get_next(seq, v);
4174 	++*pos;
4175 	return ifa;
4176 }
4177 
4178 static void if6_seq_stop(struct seq_file *seq, void *v)
4179 	__releases(rcu_bh)
4180 {
4181 	rcu_read_unlock_bh();
4182 }
4183 
4184 static int if6_seq_show(struct seq_file *seq, void *v)
4185 {
4186 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4187 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4188 		   &ifp->addr,
4189 		   ifp->idev->dev->ifindex,
4190 		   ifp->prefix_len,
4191 		   ifp->scope,
4192 		   (u8) ifp->flags,
4193 		   ifp->idev->dev->name);
4194 	return 0;
4195 }
4196 
4197 static const struct seq_operations if6_seq_ops = {
4198 	.start	= if6_seq_start,
4199 	.next	= if6_seq_next,
4200 	.show	= if6_seq_show,
4201 	.stop	= if6_seq_stop,
4202 };
4203 
4204 static int if6_seq_open(struct inode *inode, struct file *file)
4205 {
4206 	return seq_open_net(inode, file, &if6_seq_ops,
4207 			    sizeof(struct if6_iter_state));
4208 }
4209 
4210 static const struct file_operations if6_fops = {
4211 	.owner		= THIS_MODULE,
4212 	.open		= if6_seq_open,
4213 	.read		= seq_read,
4214 	.llseek		= seq_lseek,
4215 	.release	= seq_release_net,
4216 };
4217 
4218 static int __net_init if6_proc_net_init(struct net *net)
4219 {
4220 	if (!proc_create("if_inet6", S_IRUGO, net->proc_net, &if6_fops))
4221 		return -ENOMEM;
4222 	return 0;
4223 }
4224 
4225 static void __net_exit if6_proc_net_exit(struct net *net)
4226 {
4227 	remove_proc_entry("if_inet6", net->proc_net);
4228 }
4229 
4230 static struct pernet_operations if6_proc_net_ops = {
4231 	.init = if6_proc_net_init,
4232 	.exit = if6_proc_net_exit,
4233 };
4234 
4235 int __init if6_proc_init(void)
4236 {
4237 	return register_pernet_subsys(&if6_proc_net_ops);
4238 }
4239 
4240 void if6_proc_exit(void)
4241 {
4242 	unregister_pernet_subsys(&if6_proc_net_ops);
4243 }
4244 #endif	/* CONFIG_PROC_FS */
4245 
4246 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4247 /* Check if address is a home address configured on any interface. */
4248 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4249 {
4250 	int ret = 0;
4251 	struct inet6_ifaddr *ifp = NULL;
4252 	unsigned int hash = inet6_addr_hash(addr);
4253 
4254 	rcu_read_lock_bh();
4255 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
4256 		if (!net_eq(dev_net(ifp->idev->dev), net))
4257 			continue;
4258 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4259 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4260 			ret = 1;
4261 			break;
4262 		}
4263 	}
4264 	rcu_read_unlock_bh();
4265 	return ret;
4266 }
4267 #endif
4268 
4269 /*
4270  *	Periodic address status verification
4271  */
4272 
4273 static void addrconf_verify_rtnl(void)
4274 {
4275 	unsigned long now, next, next_sec, next_sched;
4276 	struct inet6_ifaddr *ifp;
4277 	int i;
4278 
4279 	ASSERT_RTNL();
4280 
4281 	rcu_read_lock_bh();
4282 	now = jiffies;
4283 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4284 
4285 	cancel_delayed_work(&addr_chk_work);
4286 
4287 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4288 restart:
4289 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4290 			unsigned long age;
4291 
4292 			/* When setting preferred_lft to a value not zero or
4293 			 * infinity, while valid_lft is infinity
4294 			 * IFA_F_PERMANENT has a non-infinity life time.
4295 			 */
4296 			if ((ifp->flags & IFA_F_PERMANENT) &&
4297 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4298 				continue;
4299 
4300 			spin_lock(&ifp->lock);
4301 			/* We try to batch several events at once. */
4302 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4303 
4304 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4305 			    age >= ifp->valid_lft) {
4306 				spin_unlock(&ifp->lock);
4307 				in6_ifa_hold(ifp);
4308 				ipv6_del_addr(ifp);
4309 				goto restart;
4310 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4311 				spin_unlock(&ifp->lock);
4312 				continue;
4313 			} else if (age >= ifp->prefered_lft) {
4314 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4315 				int deprecate = 0;
4316 
4317 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4318 					deprecate = 1;
4319 					ifp->flags |= IFA_F_DEPRECATED;
4320 				}
4321 
4322 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4323 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4324 					next = ifp->tstamp + ifp->valid_lft * HZ;
4325 
4326 				spin_unlock(&ifp->lock);
4327 
4328 				if (deprecate) {
4329 					in6_ifa_hold(ifp);
4330 
4331 					ipv6_ifa_notify(0, ifp);
4332 					in6_ifa_put(ifp);
4333 					goto restart;
4334 				}
4335 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
4336 				   !(ifp->flags&IFA_F_TENTATIVE)) {
4337 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4338 					ifp->idev->cnf.dad_transmits *
4339 					NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
4340 
4341 				if (age >= ifp->prefered_lft - regen_advance) {
4342 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4343 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4344 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4345 					if (!ifp->regen_count && ifpub) {
4346 						ifp->regen_count++;
4347 						in6_ifa_hold(ifp);
4348 						in6_ifa_hold(ifpub);
4349 						spin_unlock(&ifp->lock);
4350 
4351 						spin_lock(&ifpub->lock);
4352 						ifpub->regen_count = 0;
4353 						spin_unlock(&ifpub->lock);
4354 						ipv6_create_tempaddr(ifpub, ifp);
4355 						in6_ifa_put(ifpub);
4356 						in6_ifa_put(ifp);
4357 						goto restart;
4358 					}
4359 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4360 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4361 				spin_unlock(&ifp->lock);
4362 			} else {
4363 				/* ifp->prefered_lft <= ifp->valid_lft */
4364 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4365 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4366 				spin_unlock(&ifp->lock);
4367 			}
4368 		}
4369 	}
4370 
4371 	next_sec = round_jiffies_up(next);
4372 	next_sched = next;
4373 
4374 	/* If rounded timeout is accurate enough, accept it. */
4375 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4376 		next_sched = next_sec;
4377 
4378 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4379 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4380 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4381 
4382 	ADBG(KERN_DEBUG "now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4383 	      now, next, next_sec, next_sched);
4384 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4385 	rcu_read_unlock_bh();
4386 }
4387 
4388 static void addrconf_verify_work(struct work_struct *w)
4389 {
4390 	rtnl_lock();
4391 	addrconf_verify_rtnl();
4392 	rtnl_unlock();
4393 }
4394 
4395 static void addrconf_verify(void)
4396 {
4397 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4398 }
4399 
4400 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4401 				     struct in6_addr **peer_pfx)
4402 {
4403 	struct in6_addr *pfx = NULL;
4404 
4405 	*peer_pfx = NULL;
4406 
4407 	if (addr)
4408 		pfx = nla_data(addr);
4409 
4410 	if (local) {
4411 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4412 			*peer_pfx = pfx;
4413 		pfx = nla_data(local);
4414 	}
4415 
4416 	return pfx;
4417 }
4418 
4419 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4420 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4421 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4422 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4423 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4424 };
4425 
4426 static int
4427 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4428 		  struct netlink_ext_ack *extack)
4429 {
4430 	struct net *net = sock_net(skb->sk);
4431 	struct ifaddrmsg *ifm;
4432 	struct nlattr *tb[IFA_MAX+1];
4433 	struct in6_addr *pfx, *peer_pfx;
4434 	u32 ifa_flags;
4435 	int err;
4436 
4437 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4438 			  extack);
4439 	if (err < 0)
4440 		return err;
4441 
4442 	ifm = nlmsg_data(nlh);
4443 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4444 	if (!pfx)
4445 		return -EINVAL;
4446 
4447 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4448 
4449 	/* We ignore other flags so far. */
4450 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4451 
4452 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4453 			      ifm->ifa_prefixlen);
4454 }
4455 
4456 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u32 ifa_flags,
4457 			     u32 prefered_lft, u32 valid_lft)
4458 {
4459 	u32 flags;
4460 	clock_t expires;
4461 	unsigned long timeout;
4462 	bool was_managetempaddr;
4463 	bool had_prefixroute;
4464 
4465 	ASSERT_RTNL();
4466 
4467 	if (!valid_lft || (prefered_lft > valid_lft))
4468 		return -EINVAL;
4469 
4470 	if (ifa_flags & IFA_F_MANAGETEMPADDR &&
4471 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4472 		return -EINVAL;
4473 
4474 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
4475 	if (addrconf_finite_timeout(timeout)) {
4476 		expires = jiffies_to_clock_t(timeout * HZ);
4477 		valid_lft = timeout;
4478 		flags = RTF_EXPIRES;
4479 	} else {
4480 		expires = 0;
4481 		flags = 0;
4482 		ifa_flags |= IFA_F_PERMANENT;
4483 	}
4484 
4485 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
4486 	if (addrconf_finite_timeout(timeout)) {
4487 		if (timeout == 0)
4488 			ifa_flags |= IFA_F_DEPRECATED;
4489 		prefered_lft = timeout;
4490 	}
4491 
4492 	spin_lock_bh(&ifp->lock);
4493 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4494 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4495 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4496 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4497 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4498 			IFA_F_NOPREFIXROUTE);
4499 	ifp->flags |= ifa_flags;
4500 	ifp->tstamp = jiffies;
4501 	ifp->valid_lft = valid_lft;
4502 	ifp->prefered_lft = prefered_lft;
4503 
4504 	spin_unlock_bh(&ifp->lock);
4505 	if (!(ifp->flags&IFA_F_TENTATIVE))
4506 		ipv6_ifa_notify(0, ifp);
4507 
4508 	if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
4509 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
4510 				      expires, flags);
4511 	} else if (had_prefixroute) {
4512 		enum cleanup_prefix_rt_t action;
4513 		unsigned long rt_expires;
4514 
4515 		write_lock_bh(&ifp->idev->lock);
4516 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4517 		write_unlock_bh(&ifp->idev->lock);
4518 
4519 		if (action != CLEANUP_PREFIX_RT_NOP) {
4520 			cleanup_prefix_route(ifp, rt_expires,
4521 				action == CLEANUP_PREFIX_RT_DEL);
4522 		}
4523 	}
4524 
4525 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4526 		if (was_managetempaddr && !(ifp->flags & IFA_F_MANAGETEMPADDR))
4527 			valid_lft = prefered_lft = 0;
4528 		manage_tempaddrs(ifp->idev, ifp, valid_lft, prefered_lft,
4529 				 !was_managetempaddr, jiffies);
4530 	}
4531 
4532 	addrconf_verify_rtnl();
4533 
4534 	return 0;
4535 }
4536 
4537 static int
4538 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4539 		  struct netlink_ext_ack *extack)
4540 {
4541 	struct net *net = sock_net(skb->sk);
4542 	struct ifaddrmsg *ifm;
4543 	struct nlattr *tb[IFA_MAX+1];
4544 	struct in6_addr *pfx, *peer_pfx;
4545 	struct inet6_ifaddr *ifa;
4546 	struct net_device *dev;
4547 	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
4548 	u32 ifa_flags;
4549 	int err;
4550 
4551 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4552 			  extack);
4553 	if (err < 0)
4554 		return err;
4555 
4556 	ifm = nlmsg_data(nlh);
4557 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4558 	if (!pfx)
4559 		return -EINVAL;
4560 
4561 	if (tb[IFA_CACHEINFO]) {
4562 		struct ifa_cacheinfo *ci;
4563 
4564 		ci = nla_data(tb[IFA_CACHEINFO]);
4565 		valid_lft = ci->ifa_valid;
4566 		preferred_lft = ci->ifa_prefered;
4567 	} else {
4568 		preferred_lft = INFINITY_LIFE_TIME;
4569 		valid_lft = INFINITY_LIFE_TIME;
4570 	}
4571 
4572 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4573 	if (!dev)
4574 		return -ENODEV;
4575 
4576 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4577 
4578 	/* We ignore other flags so far. */
4579 	ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4580 		     IFA_F_NOPREFIXROUTE | IFA_F_MCAUTOJOIN;
4581 
4582 	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
4583 	if (!ifa) {
4584 		/*
4585 		 * It would be best to check for !NLM_F_CREATE here but
4586 		 * userspace already relies on not having to provide this.
4587 		 */
4588 		return inet6_addr_add(net, ifm->ifa_index, pfx, peer_pfx,
4589 				      ifm->ifa_prefixlen, ifa_flags,
4590 				      preferred_lft, valid_lft, extack);
4591 	}
4592 
4593 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4594 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4595 		err = -EEXIST;
4596 	else
4597 		err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
4598 
4599 	in6_ifa_put(ifa);
4600 
4601 	return err;
4602 }
4603 
4604 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4605 			  u8 scope, int ifindex)
4606 {
4607 	struct ifaddrmsg *ifm;
4608 
4609 	ifm = nlmsg_data(nlh);
4610 	ifm->ifa_family = AF_INET6;
4611 	ifm->ifa_prefixlen = prefixlen;
4612 	ifm->ifa_flags = flags;
4613 	ifm->ifa_scope = scope;
4614 	ifm->ifa_index = ifindex;
4615 }
4616 
4617 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4618 			 unsigned long tstamp, u32 preferred, u32 valid)
4619 {
4620 	struct ifa_cacheinfo ci;
4621 
4622 	ci.cstamp = cstamp_delta(cstamp);
4623 	ci.tstamp = cstamp_delta(tstamp);
4624 	ci.ifa_prefered = preferred;
4625 	ci.ifa_valid = valid;
4626 
4627 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4628 }
4629 
4630 static inline int rt_scope(int ifa_scope)
4631 {
4632 	if (ifa_scope & IFA_HOST)
4633 		return RT_SCOPE_HOST;
4634 	else if (ifa_scope & IFA_LINK)
4635 		return RT_SCOPE_LINK;
4636 	else if (ifa_scope & IFA_SITE)
4637 		return RT_SCOPE_SITE;
4638 	else
4639 		return RT_SCOPE_UNIVERSE;
4640 }
4641 
4642 static inline int inet6_ifaddr_msgsize(void)
4643 {
4644 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4645 	       + nla_total_size(16) /* IFA_LOCAL */
4646 	       + nla_total_size(16) /* IFA_ADDRESS */
4647 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4648 	       + nla_total_size(4)  /* IFA_FLAGS */;
4649 }
4650 
4651 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4652 			     u32 portid, u32 seq, int event, unsigned int flags)
4653 {
4654 	struct nlmsghdr  *nlh;
4655 	u32 preferred, valid;
4656 
4657 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4658 	if (!nlh)
4659 		return -EMSGSIZE;
4660 
4661 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4662 		      ifa->idev->dev->ifindex);
4663 
4664 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4665 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4666 		preferred = ifa->prefered_lft;
4667 		valid = ifa->valid_lft;
4668 		if (preferred != INFINITY_LIFE_TIME) {
4669 			long tval = (jiffies - ifa->tstamp)/HZ;
4670 			if (preferred > tval)
4671 				preferred -= tval;
4672 			else
4673 				preferred = 0;
4674 			if (valid != INFINITY_LIFE_TIME) {
4675 				if (valid > tval)
4676 					valid -= tval;
4677 				else
4678 					valid = 0;
4679 			}
4680 		}
4681 	} else {
4682 		preferred = INFINITY_LIFE_TIME;
4683 		valid = INFINITY_LIFE_TIME;
4684 	}
4685 
4686 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4687 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4688 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
4689 			goto error;
4690 	} else
4691 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
4692 			goto error;
4693 
4694 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4695 		goto error;
4696 
4697 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
4698 		goto error;
4699 
4700 	nlmsg_end(skb, nlh);
4701 	return 0;
4702 
4703 error:
4704 	nlmsg_cancel(skb, nlh);
4705 	return -EMSGSIZE;
4706 }
4707 
4708 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
4709 				u32 portid, u32 seq, int event, u16 flags)
4710 {
4711 	struct nlmsghdr  *nlh;
4712 	u8 scope = RT_SCOPE_UNIVERSE;
4713 	int ifindex = ifmca->idev->dev->ifindex;
4714 
4715 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
4716 		scope = RT_SCOPE_SITE;
4717 
4718 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4719 	if (!nlh)
4720 		return -EMSGSIZE;
4721 
4722 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4723 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
4724 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
4725 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4726 		nlmsg_cancel(skb, nlh);
4727 		return -EMSGSIZE;
4728 	}
4729 
4730 	nlmsg_end(skb, nlh);
4731 	return 0;
4732 }
4733 
4734 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
4735 				u32 portid, u32 seq, int event, unsigned int flags)
4736 {
4737 	struct nlmsghdr  *nlh;
4738 	u8 scope = RT_SCOPE_UNIVERSE;
4739 	int ifindex = ifaca->aca_idev->dev->ifindex;
4740 
4741 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
4742 		scope = RT_SCOPE_SITE;
4743 
4744 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4745 	if (!nlh)
4746 		return -EMSGSIZE;
4747 
4748 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4749 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
4750 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
4751 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4752 		nlmsg_cancel(skb, nlh);
4753 		return -EMSGSIZE;
4754 	}
4755 
4756 	nlmsg_end(skb, nlh);
4757 	return 0;
4758 }
4759 
4760 enum addr_type_t {
4761 	UNICAST_ADDR,
4762 	MULTICAST_ADDR,
4763 	ANYCAST_ADDR,
4764 };
4765 
4766 /* called with rcu_read_lock() */
4767 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
4768 			  struct netlink_callback *cb, enum addr_type_t type,
4769 			  int s_ip_idx, int *p_ip_idx)
4770 {
4771 	struct ifmcaddr6 *ifmca;
4772 	struct ifacaddr6 *ifaca;
4773 	int err = 1;
4774 	int ip_idx = *p_ip_idx;
4775 
4776 	read_lock_bh(&idev->lock);
4777 	switch (type) {
4778 	case UNICAST_ADDR: {
4779 		struct inet6_ifaddr *ifa;
4780 
4781 		/* unicast address incl. temp addr */
4782 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
4783 			if (++ip_idx < s_ip_idx)
4784 				continue;
4785 			err = inet6_fill_ifaddr(skb, ifa,
4786 						NETLINK_CB(cb->skb).portid,
4787 						cb->nlh->nlmsg_seq,
4788 						RTM_NEWADDR,
4789 						NLM_F_MULTI);
4790 			if (err < 0)
4791 				break;
4792 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
4793 		}
4794 		break;
4795 	}
4796 	case MULTICAST_ADDR:
4797 		/* multicast address */
4798 		for (ifmca = idev->mc_list; ifmca;
4799 		     ifmca = ifmca->next, ip_idx++) {
4800 			if (ip_idx < s_ip_idx)
4801 				continue;
4802 			err = inet6_fill_ifmcaddr(skb, ifmca,
4803 						  NETLINK_CB(cb->skb).portid,
4804 						  cb->nlh->nlmsg_seq,
4805 						  RTM_GETMULTICAST,
4806 						  NLM_F_MULTI);
4807 			if (err < 0)
4808 				break;
4809 		}
4810 		break;
4811 	case ANYCAST_ADDR:
4812 		/* anycast address */
4813 		for (ifaca = idev->ac_list; ifaca;
4814 		     ifaca = ifaca->aca_next, ip_idx++) {
4815 			if (ip_idx < s_ip_idx)
4816 				continue;
4817 			err = inet6_fill_ifacaddr(skb, ifaca,
4818 						  NETLINK_CB(cb->skb).portid,
4819 						  cb->nlh->nlmsg_seq,
4820 						  RTM_GETANYCAST,
4821 						  NLM_F_MULTI);
4822 			if (err < 0)
4823 				break;
4824 		}
4825 		break;
4826 	default:
4827 		break;
4828 	}
4829 	read_unlock_bh(&idev->lock);
4830 	*p_ip_idx = ip_idx;
4831 	return err;
4832 }
4833 
4834 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
4835 			   enum addr_type_t type)
4836 {
4837 	struct net *net = sock_net(skb->sk);
4838 	int h, s_h;
4839 	int idx, ip_idx;
4840 	int s_idx, s_ip_idx;
4841 	struct net_device *dev;
4842 	struct inet6_dev *idev;
4843 	struct hlist_head *head;
4844 
4845 	s_h = cb->args[0];
4846 	s_idx = idx = cb->args[1];
4847 	s_ip_idx = ip_idx = cb->args[2];
4848 
4849 	rcu_read_lock();
4850 	cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^ net->dev_base_seq;
4851 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4852 		idx = 0;
4853 		head = &net->dev_index_head[h];
4854 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4855 			if (idx < s_idx)
4856 				goto cont;
4857 			if (h > s_h || idx > s_idx)
4858 				s_ip_idx = 0;
4859 			ip_idx = 0;
4860 			idev = __in6_dev_get(dev);
4861 			if (!idev)
4862 				goto cont;
4863 
4864 			if (in6_dump_addrs(idev, skb, cb, type,
4865 					   s_ip_idx, &ip_idx) < 0)
4866 				goto done;
4867 cont:
4868 			idx++;
4869 		}
4870 	}
4871 done:
4872 	rcu_read_unlock();
4873 	cb->args[0] = h;
4874 	cb->args[1] = idx;
4875 	cb->args[2] = ip_idx;
4876 
4877 	return skb->len;
4878 }
4879 
4880 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
4881 {
4882 	enum addr_type_t type = UNICAST_ADDR;
4883 
4884 	return inet6_dump_addr(skb, cb, type);
4885 }
4886 
4887 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
4888 {
4889 	enum addr_type_t type = MULTICAST_ADDR;
4890 
4891 	return inet6_dump_addr(skb, cb, type);
4892 }
4893 
4894 
4895 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
4896 {
4897 	enum addr_type_t type = ANYCAST_ADDR;
4898 
4899 	return inet6_dump_addr(skb, cb, type);
4900 }
4901 
4902 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
4903 			     struct netlink_ext_ack *extack)
4904 {
4905 	struct net *net = sock_net(in_skb->sk);
4906 	struct ifaddrmsg *ifm;
4907 	struct nlattr *tb[IFA_MAX+1];
4908 	struct in6_addr *addr = NULL, *peer;
4909 	struct net_device *dev = NULL;
4910 	struct inet6_ifaddr *ifa;
4911 	struct sk_buff *skb;
4912 	int err;
4913 
4914 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4915 			  extack);
4916 	if (err < 0)
4917 		return err;
4918 
4919 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
4920 	if (!addr)
4921 		return -EINVAL;
4922 
4923 	ifm = nlmsg_data(nlh);
4924 	if (ifm->ifa_index)
4925 		dev = dev_get_by_index(net, ifm->ifa_index);
4926 
4927 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
4928 	if (!ifa) {
4929 		err = -EADDRNOTAVAIL;
4930 		goto errout;
4931 	}
4932 
4933 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
4934 	if (!skb) {
4935 		err = -ENOBUFS;
4936 		goto errout_ifa;
4937 	}
4938 
4939 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
4940 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
4941 	if (err < 0) {
4942 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4943 		WARN_ON(err == -EMSGSIZE);
4944 		kfree_skb(skb);
4945 		goto errout_ifa;
4946 	}
4947 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
4948 errout_ifa:
4949 	in6_ifa_put(ifa);
4950 errout:
4951 	if (dev)
4952 		dev_put(dev);
4953 	return err;
4954 }
4955 
4956 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
4957 {
4958 	struct sk_buff *skb;
4959 	struct net *net = dev_net(ifa->idev->dev);
4960 	int err = -ENOBUFS;
4961 
4962 	/* Don't send DELADDR notification for TENTATIVE address,
4963 	 * since NEWADDR notification is sent only after removing
4964 	 * TENTATIVE flag, if DAD has not failed.
4965 	 */
4966 	if (ifa->flags & IFA_F_TENTATIVE && !(ifa->flags & IFA_F_DADFAILED) &&
4967 	    event == RTM_DELADDR)
4968 		return;
4969 
4970 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
4971 	if (!skb)
4972 		goto errout;
4973 
4974 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
4975 	if (err < 0) {
4976 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4977 		WARN_ON(err == -EMSGSIZE);
4978 		kfree_skb(skb);
4979 		goto errout;
4980 	}
4981 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
4982 	return;
4983 errout:
4984 	if (err < 0)
4985 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
4986 }
4987 
4988 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
4989 				__s32 *array, int bytes)
4990 {
4991 	BUG_ON(bytes < (DEVCONF_MAX * 4));
4992 
4993 	memset(array, 0, bytes);
4994 	array[DEVCONF_FORWARDING] = cnf->forwarding;
4995 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
4996 	array[DEVCONF_MTU6] = cnf->mtu6;
4997 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
4998 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
4999 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
5000 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
5001 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
5002 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5003 		jiffies_to_msecs(cnf->rtr_solicit_interval);
5004 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5005 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
5006 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5007 		jiffies_to_msecs(cnf->rtr_solicit_delay);
5008 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5009 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5010 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5011 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5012 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5013 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5014 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5015 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5016 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5017 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5018 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5019 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5020 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5021 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5022 #ifdef CONFIG_IPV6_ROUTER_PREF
5023 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5024 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5025 		jiffies_to_msecs(cnf->rtr_probe_interval);
5026 #ifdef CONFIG_IPV6_ROUTE_INFO
5027 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5028 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5029 #endif
5030 #endif
5031 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5032 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5033 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5034 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5035 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5036 #endif
5037 #ifdef CONFIG_IPV6_MROUTE
5038 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
5039 #endif
5040 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5041 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5042 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5043 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5044 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5045 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5046 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5047 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5048 	/* we omit DEVCONF_STABLE_SECRET for now */
5049 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5050 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5051 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5052 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5053 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5054 #ifdef CONFIG_IPV6_SEG6_HMAC
5055 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5056 #endif
5057 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5058 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5059 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5060 }
5061 
5062 static inline size_t inet6_ifla6_size(void)
5063 {
5064 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5065 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5066 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5067 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5068 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5069 	     + nla_total_size(sizeof(struct in6_addr)); /* IFLA_INET6_TOKEN */
5070 }
5071 
5072 static inline size_t inet6_if_nlmsg_size(void)
5073 {
5074 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5075 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5076 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5077 	       + nla_total_size(4) /* IFLA_MTU */
5078 	       + nla_total_size(4) /* IFLA_LINK */
5079 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5080 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5081 }
5082 
5083 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5084 					int bytes)
5085 {
5086 	int i;
5087 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5088 	BUG_ON(pad < 0);
5089 
5090 	/* Use put_unaligned() because stats may not be aligned for u64. */
5091 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5092 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5093 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5094 
5095 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5096 }
5097 
5098 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5099 					int bytes, size_t syncpoff)
5100 {
5101 	int i, c;
5102 	u64 buff[IPSTATS_MIB_MAX];
5103 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5104 
5105 	BUG_ON(pad < 0);
5106 
5107 	memset(buff, 0, sizeof(buff));
5108 	buff[0] = IPSTATS_MIB_MAX;
5109 
5110 	for_each_possible_cpu(c) {
5111 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5112 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5113 	}
5114 
5115 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5116 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5117 }
5118 
5119 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5120 			     int bytes)
5121 {
5122 	switch (attrtype) {
5123 	case IFLA_INET6_STATS:
5124 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5125 				     offsetof(struct ipstats_mib, syncp));
5126 		break;
5127 	case IFLA_INET6_ICMP6STATS:
5128 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5129 		break;
5130 	}
5131 }
5132 
5133 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5134 				  u32 ext_filter_mask)
5135 {
5136 	struct nlattr *nla;
5137 	struct ifla_cacheinfo ci;
5138 
5139 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5140 		goto nla_put_failure;
5141 	ci.max_reasm_len = IPV6_MAXPLEN;
5142 	ci.tstamp = cstamp_delta(idev->tstamp);
5143 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5144 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5145 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5146 		goto nla_put_failure;
5147 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5148 	if (!nla)
5149 		goto nla_put_failure;
5150 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5151 
5152 	/* XXX - MC not implemented */
5153 
5154 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5155 		return 0;
5156 
5157 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5158 	if (!nla)
5159 		goto nla_put_failure;
5160 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5161 
5162 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5163 	if (!nla)
5164 		goto nla_put_failure;
5165 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5166 
5167 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5168 	if (!nla)
5169 		goto nla_put_failure;
5170 
5171 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5172 		goto nla_put_failure;
5173 
5174 	read_lock_bh(&idev->lock);
5175 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5176 	read_unlock_bh(&idev->lock);
5177 
5178 	return 0;
5179 
5180 nla_put_failure:
5181 	return -EMSGSIZE;
5182 }
5183 
5184 static size_t inet6_get_link_af_size(const struct net_device *dev,
5185 				     u32 ext_filter_mask)
5186 {
5187 	if (!__in6_dev_get(dev))
5188 		return 0;
5189 
5190 	return inet6_ifla6_size();
5191 }
5192 
5193 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5194 			      u32 ext_filter_mask)
5195 {
5196 	struct inet6_dev *idev = __in6_dev_get(dev);
5197 
5198 	if (!idev)
5199 		return -ENODATA;
5200 
5201 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5202 		return -EMSGSIZE;
5203 
5204 	return 0;
5205 }
5206 
5207 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
5208 {
5209 	struct inet6_ifaddr *ifp;
5210 	struct net_device *dev = idev->dev;
5211 	bool clear_token, update_rs = false;
5212 	struct in6_addr ll_addr;
5213 
5214 	ASSERT_RTNL();
5215 
5216 	if (!token)
5217 		return -EINVAL;
5218 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
5219 		return -EINVAL;
5220 	if (!ipv6_accept_ra(idev))
5221 		return -EINVAL;
5222 	if (idev->cnf.rtr_solicits == 0)
5223 		return -EINVAL;
5224 
5225 	write_lock_bh(&idev->lock);
5226 
5227 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5228 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5229 
5230 	write_unlock_bh(&idev->lock);
5231 
5232 	clear_token = ipv6_addr_any(token);
5233 	if (clear_token)
5234 		goto update_lft;
5235 
5236 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5237 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5238 			     IFA_F_OPTIMISTIC)) {
5239 		/* If we're not ready, then normal ifup will take care
5240 		 * of this. Otherwise, we need to request our rs here.
5241 		 */
5242 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5243 		update_rs = true;
5244 	}
5245 
5246 update_lft:
5247 	write_lock_bh(&idev->lock);
5248 
5249 	if (update_rs) {
5250 		idev->if_flags |= IF_RS_SENT;
5251 		idev->rs_interval = rfc3315_s14_backoff_init(
5252 			idev->cnf.rtr_solicit_interval);
5253 		idev->rs_probes = 1;
5254 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5255 	}
5256 
5257 	/* Well, that's kinda nasty ... */
5258 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5259 		spin_lock(&ifp->lock);
5260 		if (ifp->tokenized) {
5261 			ifp->valid_lft = 0;
5262 			ifp->prefered_lft = 0;
5263 		}
5264 		spin_unlock(&ifp->lock);
5265 	}
5266 
5267 	write_unlock_bh(&idev->lock);
5268 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5269 	addrconf_verify_rtnl();
5270 	return 0;
5271 }
5272 
5273 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5274 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5275 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5276 };
5277 
5278 static int inet6_validate_link_af(const struct net_device *dev,
5279 				  const struct nlattr *nla)
5280 {
5281 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5282 
5283 	if (dev && !__in6_dev_get(dev))
5284 		return -EAFNOSUPPORT;
5285 
5286 	return nla_parse_nested(tb, IFLA_INET6_MAX, nla, inet6_af_policy,
5287 				NULL);
5288 }
5289 
5290 static int check_addr_gen_mode(int mode)
5291 {
5292 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5293 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5294 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5295 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5296 		return -EINVAL;
5297 	return 1;
5298 }
5299 
5300 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5301 				int mode)
5302 {
5303 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5304 	    !idev->cnf.stable_secret.initialized &&
5305 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5306 		return -EINVAL;
5307 	return 1;
5308 }
5309 
5310 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
5311 {
5312 	int err = -EINVAL;
5313 	struct inet6_dev *idev = __in6_dev_get(dev);
5314 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5315 
5316 	if (!idev)
5317 		return -EAFNOSUPPORT;
5318 
5319 	if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5320 		BUG();
5321 
5322 	if (tb[IFLA_INET6_TOKEN]) {
5323 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
5324 		if (err)
5325 			return err;
5326 	}
5327 
5328 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5329 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5330 
5331 		if (check_addr_gen_mode(mode) < 0 ||
5332 		    check_stable_privacy(idev, dev_net(dev), mode) < 0)
5333 			return -EINVAL;
5334 
5335 		idev->cnf.addr_gen_mode = mode;
5336 		err = 0;
5337 	}
5338 
5339 	return err;
5340 }
5341 
5342 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5343 			     u32 portid, u32 seq, int event, unsigned int flags)
5344 {
5345 	struct net_device *dev = idev->dev;
5346 	struct ifinfomsg *hdr;
5347 	struct nlmsghdr *nlh;
5348 	void *protoinfo;
5349 
5350 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5351 	if (!nlh)
5352 		return -EMSGSIZE;
5353 
5354 	hdr = nlmsg_data(nlh);
5355 	hdr->ifi_family = AF_INET6;
5356 	hdr->__ifi_pad = 0;
5357 	hdr->ifi_type = dev->type;
5358 	hdr->ifi_index = dev->ifindex;
5359 	hdr->ifi_flags = dev_get_flags(dev);
5360 	hdr->ifi_change = 0;
5361 
5362 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5363 	    (dev->addr_len &&
5364 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5365 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5366 	    (dev->ifindex != dev_get_iflink(dev) &&
5367 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5368 	    nla_put_u8(skb, IFLA_OPERSTATE,
5369 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5370 		goto nla_put_failure;
5371 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
5372 	if (!protoinfo)
5373 		goto nla_put_failure;
5374 
5375 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5376 		goto nla_put_failure;
5377 
5378 	nla_nest_end(skb, protoinfo);
5379 	nlmsg_end(skb, nlh);
5380 	return 0;
5381 
5382 nla_put_failure:
5383 	nlmsg_cancel(skb, nlh);
5384 	return -EMSGSIZE;
5385 }
5386 
5387 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5388 {
5389 	struct net *net = sock_net(skb->sk);
5390 	int h, s_h;
5391 	int idx = 0, s_idx;
5392 	struct net_device *dev;
5393 	struct inet6_dev *idev;
5394 	struct hlist_head *head;
5395 
5396 	s_h = cb->args[0];
5397 	s_idx = cb->args[1];
5398 
5399 	rcu_read_lock();
5400 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5401 		idx = 0;
5402 		head = &net->dev_index_head[h];
5403 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5404 			if (idx < s_idx)
5405 				goto cont;
5406 			idev = __in6_dev_get(dev);
5407 			if (!idev)
5408 				goto cont;
5409 			if (inet6_fill_ifinfo(skb, idev,
5410 					      NETLINK_CB(cb->skb).portid,
5411 					      cb->nlh->nlmsg_seq,
5412 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
5413 				goto out;
5414 cont:
5415 			idx++;
5416 		}
5417 	}
5418 out:
5419 	rcu_read_unlock();
5420 	cb->args[1] = idx;
5421 	cb->args[0] = h;
5422 
5423 	return skb->len;
5424 }
5425 
5426 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5427 {
5428 	struct sk_buff *skb;
5429 	struct net *net = dev_net(idev->dev);
5430 	int err = -ENOBUFS;
5431 
5432 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5433 	if (!skb)
5434 		goto errout;
5435 
5436 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5437 	if (err < 0) {
5438 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5439 		WARN_ON(err == -EMSGSIZE);
5440 		kfree_skb(skb);
5441 		goto errout;
5442 	}
5443 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
5444 	return;
5445 errout:
5446 	if (err < 0)
5447 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
5448 }
5449 
5450 static inline size_t inet6_prefix_nlmsg_size(void)
5451 {
5452 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
5453 	       + nla_total_size(sizeof(struct in6_addr))
5454 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
5455 }
5456 
5457 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
5458 			     struct prefix_info *pinfo, u32 portid, u32 seq,
5459 			     int event, unsigned int flags)
5460 {
5461 	struct prefixmsg *pmsg;
5462 	struct nlmsghdr *nlh;
5463 	struct prefix_cacheinfo	ci;
5464 
5465 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
5466 	if (!nlh)
5467 		return -EMSGSIZE;
5468 
5469 	pmsg = nlmsg_data(nlh);
5470 	pmsg->prefix_family = AF_INET6;
5471 	pmsg->prefix_pad1 = 0;
5472 	pmsg->prefix_pad2 = 0;
5473 	pmsg->prefix_ifindex = idev->dev->ifindex;
5474 	pmsg->prefix_len = pinfo->prefix_len;
5475 	pmsg->prefix_type = pinfo->type;
5476 	pmsg->prefix_pad3 = 0;
5477 	pmsg->prefix_flags = 0;
5478 	if (pinfo->onlink)
5479 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
5480 	if (pinfo->autoconf)
5481 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
5482 
5483 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
5484 		goto nla_put_failure;
5485 	ci.preferred_time = ntohl(pinfo->prefered);
5486 	ci.valid_time = ntohl(pinfo->valid);
5487 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
5488 		goto nla_put_failure;
5489 	nlmsg_end(skb, nlh);
5490 	return 0;
5491 
5492 nla_put_failure:
5493 	nlmsg_cancel(skb, nlh);
5494 	return -EMSGSIZE;
5495 }
5496 
5497 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
5498 			 struct prefix_info *pinfo)
5499 {
5500 	struct sk_buff *skb;
5501 	struct net *net = dev_net(idev->dev);
5502 	int err = -ENOBUFS;
5503 
5504 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
5505 	if (!skb)
5506 		goto errout;
5507 
5508 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
5509 	if (err < 0) {
5510 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
5511 		WARN_ON(err == -EMSGSIZE);
5512 		kfree_skb(skb);
5513 		goto errout;
5514 	}
5515 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
5516 	return;
5517 errout:
5518 	if (err < 0)
5519 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
5520 }
5521 
5522 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5523 {
5524 	struct net *net = dev_net(ifp->idev->dev);
5525 
5526 	if (event)
5527 		ASSERT_RTNL();
5528 
5529 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
5530 
5531 	switch (event) {
5532 	case RTM_NEWADDR:
5533 		/*
5534 		 * If the address was optimistic
5535 		 * we inserted the route at the start of
5536 		 * our DAD process, so we don't need
5537 		 * to do it again
5538 		 */
5539 		if (!rcu_access_pointer(ifp->rt->rt6i_node))
5540 			ip6_ins_rt(ifp->rt);
5541 		if (ifp->idev->cnf.forwarding)
5542 			addrconf_join_anycast(ifp);
5543 		if (!ipv6_addr_any(&ifp->peer_addr))
5544 			addrconf_prefix_route(&ifp->peer_addr, 128,
5545 					      ifp->idev->dev, 0, 0);
5546 		break;
5547 	case RTM_DELADDR:
5548 		if (ifp->idev->cnf.forwarding)
5549 			addrconf_leave_anycast(ifp);
5550 		addrconf_leave_solict(ifp->idev, &ifp->addr);
5551 		if (!ipv6_addr_any(&ifp->peer_addr)) {
5552 			struct rt6_info *rt;
5553 
5554 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
5555 						       ifp->idev->dev, 0, 0);
5556 			if (rt)
5557 				ip6_del_rt(rt);
5558 		}
5559 		if (ifp->rt) {
5560 			if (dst_hold_safe(&ifp->rt->dst))
5561 				ip6_del_rt(ifp->rt);
5562 		}
5563 		rt_genid_bump_ipv6(net);
5564 		break;
5565 	}
5566 	atomic_inc(&net->ipv6.dev_addr_genid);
5567 }
5568 
5569 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5570 {
5571 	rcu_read_lock_bh();
5572 	if (likely(ifp->idev->dead == 0))
5573 		__ipv6_ifa_notify(event, ifp);
5574 	rcu_read_unlock_bh();
5575 }
5576 
5577 #ifdef CONFIG_SYSCTL
5578 
5579 static
5580 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
5581 			   void __user *buffer, size_t *lenp, loff_t *ppos)
5582 {
5583 	int *valp = ctl->data;
5584 	int val = *valp;
5585 	loff_t pos = *ppos;
5586 	struct ctl_table lctl;
5587 	int ret;
5588 
5589 	/*
5590 	 * ctl->data points to idev->cnf.forwarding, we should
5591 	 * not modify it until we get the rtnl lock.
5592 	 */
5593 	lctl = *ctl;
5594 	lctl.data = &val;
5595 
5596 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5597 
5598 	if (write)
5599 		ret = addrconf_fixup_forwarding(ctl, valp, val);
5600 	if (ret)
5601 		*ppos = pos;
5602 	return ret;
5603 }
5604 
5605 static
5606 int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
5607 			void __user *buffer, size_t *lenp, loff_t *ppos)
5608 {
5609 	struct inet6_dev *idev = ctl->extra1;
5610 	int min_mtu = IPV6_MIN_MTU;
5611 	struct ctl_table lctl;
5612 
5613 	lctl = *ctl;
5614 	lctl.extra1 = &min_mtu;
5615 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
5616 
5617 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
5618 }
5619 
5620 static void dev_disable_change(struct inet6_dev *idev)
5621 {
5622 	struct netdev_notifier_info info;
5623 
5624 	if (!idev || !idev->dev)
5625 		return;
5626 
5627 	netdev_notifier_info_init(&info, idev->dev);
5628 	if (idev->cnf.disable_ipv6)
5629 		addrconf_notify(NULL, NETDEV_DOWN, &info);
5630 	else
5631 		addrconf_notify(NULL, NETDEV_UP, &info);
5632 }
5633 
5634 static void addrconf_disable_change(struct net *net, __s32 newf)
5635 {
5636 	struct net_device *dev;
5637 	struct inet6_dev *idev;
5638 
5639 	for_each_netdev(net, dev) {
5640 		idev = __in6_dev_get(dev);
5641 		if (idev) {
5642 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
5643 			idev->cnf.disable_ipv6 = newf;
5644 			if (changed)
5645 				dev_disable_change(idev);
5646 		}
5647 	}
5648 }
5649 
5650 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
5651 {
5652 	struct net *net;
5653 	int old;
5654 
5655 	if (!rtnl_trylock())
5656 		return restart_syscall();
5657 
5658 	net = (struct net *)table->extra2;
5659 	old = *p;
5660 	*p = newf;
5661 
5662 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
5663 		rtnl_unlock();
5664 		return 0;
5665 	}
5666 
5667 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
5668 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
5669 		addrconf_disable_change(net, newf);
5670 	} else if ((!newf) ^ (!old))
5671 		dev_disable_change((struct inet6_dev *)table->extra1);
5672 
5673 	rtnl_unlock();
5674 	return 0;
5675 }
5676 
5677 static
5678 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
5679 			    void __user *buffer, size_t *lenp, loff_t *ppos)
5680 {
5681 	int *valp = ctl->data;
5682 	int val = *valp;
5683 	loff_t pos = *ppos;
5684 	struct ctl_table lctl;
5685 	int ret;
5686 
5687 	/*
5688 	 * ctl->data points to idev->cnf.disable_ipv6, we should
5689 	 * not modify it until we get the rtnl lock.
5690 	 */
5691 	lctl = *ctl;
5692 	lctl.data = &val;
5693 
5694 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5695 
5696 	if (write)
5697 		ret = addrconf_disable_ipv6(ctl, valp, val);
5698 	if (ret)
5699 		*ppos = pos;
5700 	return ret;
5701 }
5702 
5703 static
5704 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
5705 			      void __user *buffer, size_t *lenp, loff_t *ppos)
5706 {
5707 	int *valp = ctl->data;
5708 	int ret;
5709 	int old, new;
5710 
5711 	old = *valp;
5712 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
5713 	new = *valp;
5714 
5715 	if (write && old != new) {
5716 		struct net *net = ctl->extra2;
5717 
5718 		if (!rtnl_trylock())
5719 			return restart_syscall();
5720 
5721 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
5722 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5723 						     NETCONFA_PROXY_NEIGH,
5724 						     NETCONFA_IFINDEX_DEFAULT,
5725 						     net->ipv6.devconf_dflt);
5726 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
5727 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5728 						     NETCONFA_PROXY_NEIGH,
5729 						     NETCONFA_IFINDEX_ALL,
5730 						     net->ipv6.devconf_all);
5731 		else {
5732 			struct inet6_dev *idev = ctl->extra1;
5733 
5734 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5735 						     NETCONFA_PROXY_NEIGH,
5736 						     idev->dev->ifindex,
5737 						     &idev->cnf);
5738 		}
5739 		rtnl_unlock();
5740 	}
5741 
5742 	return ret;
5743 }
5744 
5745 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
5746 					 void __user *buffer, size_t *lenp,
5747 					 loff_t *ppos)
5748 {
5749 	int ret = 0;
5750 	int new_val;
5751 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
5752 	struct net *net = (struct net *)ctl->extra2;
5753 
5754 	if (!rtnl_trylock())
5755 		return restart_syscall();
5756 
5757 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
5758 
5759 	if (write) {
5760 		new_val = *((int *)ctl->data);
5761 
5762 		if (check_addr_gen_mode(new_val) < 0) {
5763 			ret = -EINVAL;
5764 			goto out;
5765 		}
5766 
5767 		/* request for default */
5768 		if (&net->ipv6.devconf_dflt->addr_gen_mode == ctl->data) {
5769 			ipv6_devconf_dflt.addr_gen_mode = new_val;
5770 
5771 		/* request for individual net device */
5772 		} else {
5773 			if (!idev)
5774 				goto out;
5775 
5776 			if (check_stable_privacy(idev, net, new_val) < 0) {
5777 				ret = -EINVAL;
5778 				goto out;
5779 			}
5780 
5781 			if (idev->cnf.addr_gen_mode != new_val) {
5782 				idev->cnf.addr_gen_mode = new_val;
5783 				addrconf_dev_config(idev->dev);
5784 			}
5785 		}
5786 	}
5787 
5788 out:
5789 	rtnl_unlock();
5790 
5791 	return ret;
5792 }
5793 
5794 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
5795 					 void __user *buffer, size_t *lenp,
5796 					 loff_t *ppos)
5797 {
5798 	int err;
5799 	struct in6_addr addr;
5800 	char str[IPV6_MAX_STRLEN];
5801 	struct ctl_table lctl = *ctl;
5802 	struct net *net = ctl->extra2;
5803 	struct ipv6_stable_secret *secret = ctl->data;
5804 
5805 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
5806 		return -EIO;
5807 
5808 	lctl.maxlen = IPV6_MAX_STRLEN;
5809 	lctl.data = str;
5810 
5811 	if (!rtnl_trylock())
5812 		return restart_syscall();
5813 
5814 	if (!write && !secret->initialized) {
5815 		err = -EIO;
5816 		goto out;
5817 	}
5818 
5819 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
5820 	if (err >= sizeof(str)) {
5821 		err = -EIO;
5822 		goto out;
5823 	}
5824 
5825 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
5826 	if (err || !write)
5827 		goto out;
5828 
5829 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
5830 		err = -EIO;
5831 		goto out;
5832 	}
5833 
5834 	secret->initialized = true;
5835 	secret->secret = addr;
5836 
5837 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
5838 		struct net_device *dev;
5839 
5840 		for_each_netdev(net, dev) {
5841 			struct inet6_dev *idev = __in6_dev_get(dev);
5842 
5843 			if (idev) {
5844 				idev->cnf.addr_gen_mode =
5845 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
5846 			}
5847 		}
5848 	} else {
5849 		struct inet6_dev *idev = ctl->extra1;
5850 
5851 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
5852 	}
5853 
5854 out:
5855 	rtnl_unlock();
5856 
5857 	return err;
5858 }
5859 
5860 static
5861 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
5862 						int write,
5863 						void __user *buffer,
5864 						size_t *lenp,
5865 						loff_t *ppos)
5866 {
5867 	int *valp = ctl->data;
5868 	int val = *valp;
5869 	loff_t pos = *ppos;
5870 	struct ctl_table lctl;
5871 	int ret;
5872 
5873 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
5874 	 * we should not modify it until we get the rtnl lock.
5875 	 */
5876 	lctl = *ctl;
5877 	lctl.data = &val;
5878 
5879 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5880 
5881 	if (write)
5882 		ret = addrconf_fixup_linkdown(ctl, valp, val);
5883 	if (ret)
5884 		*ppos = pos;
5885 	return ret;
5886 }
5887 
5888 static
5889 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
5890 {
5891 	if (rt) {
5892 		if (action)
5893 			rt->dst.flags |= DST_NOPOLICY;
5894 		else
5895 			rt->dst.flags &= ~DST_NOPOLICY;
5896 	}
5897 }
5898 
5899 static
5900 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
5901 {
5902 	struct inet6_ifaddr *ifa;
5903 
5904 	read_lock_bh(&idev->lock);
5905 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
5906 		spin_lock(&ifa->lock);
5907 		if (ifa->rt) {
5908 			struct rt6_info *rt = ifa->rt;
5909 			int cpu;
5910 
5911 			rcu_read_lock();
5912 			addrconf_set_nopolicy(ifa->rt, val);
5913 			if (rt->rt6i_pcpu) {
5914 				for_each_possible_cpu(cpu) {
5915 					struct rt6_info **rtp;
5916 
5917 					rtp = per_cpu_ptr(rt->rt6i_pcpu, cpu);
5918 					addrconf_set_nopolicy(*rtp, val);
5919 				}
5920 			}
5921 			rcu_read_unlock();
5922 		}
5923 		spin_unlock(&ifa->lock);
5924 	}
5925 	read_unlock_bh(&idev->lock);
5926 }
5927 
5928 static
5929 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
5930 {
5931 	struct inet6_dev *idev;
5932 	struct net *net;
5933 
5934 	if (!rtnl_trylock())
5935 		return restart_syscall();
5936 
5937 	*valp = val;
5938 
5939 	net = (struct net *)ctl->extra2;
5940 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
5941 		rtnl_unlock();
5942 		return 0;
5943 	}
5944 
5945 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
5946 		struct net_device *dev;
5947 
5948 		for_each_netdev(net, dev) {
5949 			idev = __in6_dev_get(dev);
5950 			if (idev)
5951 				addrconf_disable_policy_idev(idev, val);
5952 		}
5953 	} else {
5954 		idev = (struct inet6_dev *)ctl->extra1;
5955 		addrconf_disable_policy_idev(idev, val);
5956 	}
5957 
5958 	rtnl_unlock();
5959 	return 0;
5960 }
5961 
5962 static
5963 int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
5964 				   void __user *buffer, size_t *lenp,
5965 				   loff_t *ppos)
5966 {
5967 	int *valp = ctl->data;
5968 	int val = *valp;
5969 	loff_t pos = *ppos;
5970 	struct ctl_table lctl;
5971 	int ret;
5972 
5973 	lctl = *ctl;
5974 	lctl.data = &val;
5975 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5976 
5977 	if (write && (*valp != val))
5978 		ret = addrconf_disable_policy(ctl, valp, val);
5979 
5980 	if (ret)
5981 		*ppos = pos;
5982 
5983 	return ret;
5984 }
5985 
5986 static int minus_one = -1;
5987 static const int one = 1;
5988 static const int two_five_five = 255;
5989 
5990 static const struct ctl_table addrconf_sysctl[] = {
5991 	{
5992 		.procname	= "forwarding",
5993 		.data		= &ipv6_devconf.forwarding,
5994 		.maxlen		= sizeof(int),
5995 		.mode		= 0644,
5996 		.proc_handler	= addrconf_sysctl_forward,
5997 	},
5998 	{
5999 		.procname	= "hop_limit",
6000 		.data		= &ipv6_devconf.hop_limit,
6001 		.maxlen		= sizeof(int),
6002 		.mode		= 0644,
6003 		.proc_handler	= proc_dointvec_minmax,
6004 		.extra1		= (void *)&one,
6005 		.extra2		= (void *)&two_five_five,
6006 	},
6007 	{
6008 		.procname	= "mtu",
6009 		.data		= &ipv6_devconf.mtu6,
6010 		.maxlen		= sizeof(int),
6011 		.mode		= 0644,
6012 		.proc_handler	= addrconf_sysctl_mtu,
6013 	},
6014 	{
6015 		.procname	= "accept_ra",
6016 		.data		= &ipv6_devconf.accept_ra,
6017 		.maxlen		= sizeof(int),
6018 		.mode		= 0644,
6019 		.proc_handler	= proc_dointvec,
6020 	},
6021 	{
6022 		.procname	= "accept_redirects",
6023 		.data		= &ipv6_devconf.accept_redirects,
6024 		.maxlen		= sizeof(int),
6025 		.mode		= 0644,
6026 		.proc_handler	= proc_dointvec,
6027 	},
6028 	{
6029 		.procname	= "autoconf",
6030 		.data		= &ipv6_devconf.autoconf,
6031 		.maxlen		= sizeof(int),
6032 		.mode		= 0644,
6033 		.proc_handler	= proc_dointvec,
6034 	},
6035 	{
6036 		.procname	= "dad_transmits",
6037 		.data		= &ipv6_devconf.dad_transmits,
6038 		.maxlen		= sizeof(int),
6039 		.mode		= 0644,
6040 		.proc_handler	= proc_dointvec,
6041 	},
6042 	{
6043 		.procname	= "router_solicitations",
6044 		.data		= &ipv6_devconf.rtr_solicits,
6045 		.maxlen		= sizeof(int),
6046 		.mode		= 0644,
6047 		.proc_handler	= proc_dointvec_minmax,
6048 		.extra1		= &minus_one,
6049 	},
6050 	{
6051 		.procname	= "router_solicitation_interval",
6052 		.data		= &ipv6_devconf.rtr_solicit_interval,
6053 		.maxlen		= sizeof(int),
6054 		.mode		= 0644,
6055 		.proc_handler	= proc_dointvec_jiffies,
6056 	},
6057 	{
6058 		.procname	= "router_solicitation_max_interval",
6059 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6060 		.maxlen		= sizeof(int),
6061 		.mode		= 0644,
6062 		.proc_handler	= proc_dointvec_jiffies,
6063 	},
6064 	{
6065 		.procname	= "router_solicitation_delay",
6066 		.data		= &ipv6_devconf.rtr_solicit_delay,
6067 		.maxlen		= sizeof(int),
6068 		.mode		= 0644,
6069 		.proc_handler	= proc_dointvec_jiffies,
6070 	},
6071 	{
6072 		.procname	= "force_mld_version",
6073 		.data		= &ipv6_devconf.force_mld_version,
6074 		.maxlen		= sizeof(int),
6075 		.mode		= 0644,
6076 		.proc_handler	= proc_dointvec,
6077 	},
6078 	{
6079 		.procname	= "mldv1_unsolicited_report_interval",
6080 		.data		=
6081 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6082 		.maxlen		= sizeof(int),
6083 		.mode		= 0644,
6084 		.proc_handler	= proc_dointvec_ms_jiffies,
6085 	},
6086 	{
6087 		.procname	= "mldv2_unsolicited_report_interval",
6088 		.data		=
6089 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6090 		.maxlen		= sizeof(int),
6091 		.mode		= 0644,
6092 		.proc_handler	= proc_dointvec_ms_jiffies,
6093 	},
6094 	{
6095 		.procname	= "use_tempaddr",
6096 		.data		= &ipv6_devconf.use_tempaddr,
6097 		.maxlen		= sizeof(int),
6098 		.mode		= 0644,
6099 		.proc_handler	= proc_dointvec,
6100 	},
6101 	{
6102 		.procname	= "temp_valid_lft",
6103 		.data		= &ipv6_devconf.temp_valid_lft,
6104 		.maxlen		= sizeof(int),
6105 		.mode		= 0644,
6106 		.proc_handler	= proc_dointvec,
6107 	},
6108 	{
6109 		.procname	= "temp_prefered_lft",
6110 		.data		= &ipv6_devconf.temp_prefered_lft,
6111 		.maxlen		= sizeof(int),
6112 		.mode		= 0644,
6113 		.proc_handler	= proc_dointvec,
6114 	},
6115 	{
6116 		.procname	= "regen_max_retry",
6117 		.data		= &ipv6_devconf.regen_max_retry,
6118 		.maxlen		= sizeof(int),
6119 		.mode		= 0644,
6120 		.proc_handler	= proc_dointvec,
6121 	},
6122 	{
6123 		.procname	= "max_desync_factor",
6124 		.data		= &ipv6_devconf.max_desync_factor,
6125 		.maxlen		= sizeof(int),
6126 		.mode		= 0644,
6127 		.proc_handler	= proc_dointvec,
6128 	},
6129 	{
6130 		.procname	= "max_addresses",
6131 		.data		= &ipv6_devconf.max_addresses,
6132 		.maxlen		= sizeof(int),
6133 		.mode		= 0644,
6134 		.proc_handler	= proc_dointvec,
6135 	},
6136 	{
6137 		.procname	= "accept_ra_defrtr",
6138 		.data		= &ipv6_devconf.accept_ra_defrtr,
6139 		.maxlen		= sizeof(int),
6140 		.mode		= 0644,
6141 		.proc_handler	= proc_dointvec,
6142 	},
6143 	{
6144 		.procname	= "accept_ra_min_hop_limit",
6145 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6146 		.maxlen		= sizeof(int),
6147 		.mode		= 0644,
6148 		.proc_handler	= proc_dointvec,
6149 	},
6150 	{
6151 		.procname	= "accept_ra_pinfo",
6152 		.data		= &ipv6_devconf.accept_ra_pinfo,
6153 		.maxlen		= sizeof(int),
6154 		.mode		= 0644,
6155 		.proc_handler	= proc_dointvec,
6156 	},
6157 #ifdef CONFIG_IPV6_ROUTER_PREF
6158 	{
6159 		.procname	= "accept_ra_rtr_pref",
6160 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6161 		.maxlen		= sizeof(int),
6162 		.mode		= 0644,
6163 		.proc_handler	= proc_dointvec,
6164 	},
6165 	{
6166 		.procname	= "router_probe_interval",
6167 		.data		= &ipv6_devconf.rtr_probe_interval,
6168 		.maxlen		= sizeof(int),
6169 		.mode		= 0644,
6170 		.proc_handler	= proc_dointvec_jiffies,
6171 	},
6172 #ifdef CONFIG_IPV6_ROUTE_INFO
6173 	{
6174 		.procname	= "accept_ra_rt_info_min_plen",
6175 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6176 		.maxlen		= sizeof(int),
6177 		.mode		= 0644,
6178 		.proc_handler	= proc_dointvec,
6179 	},
6180 	{
6181 		.procname	= "accept_ra_rt_info_max_plen",
6182 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6183 		.maxlen		= sizeof(int),
6184 		.mode		= 0644,
6185 		.proc_handler	= proc_dointvec,
6186 	},
6187 #endif
6188 #endif
6189 	{
6190 		.procname	= "proxy_ndp",
6191 		.data		= &ipv6_devconf.proxy_ndp,
6192 		.maxlen		= sizeof(int),
6193 		.mode		= 0644,
6194 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6195 	},
6196 	{
6197 		.procname	= "accept_source_route",
6198 		.data		= &ipv6_devconf.accept_source_route,
6199 		.maxlen		= sizeof(int),
6200 		.mode		= 0644,
6201 		.proc_handler	= proc_dointvec,
6202 	},
6203 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6204 	{
6205 		.procname	= "optimistic_dad",
6206 		.data		= &ipv6_devconf.optimistic_dad,
6207 		.maxlen		= sizeof(int),
6208 		.mode		= 0644,
6209 		.proc_handler   = proc_dointvec,
6210 	},
6211 	{
6212 		.procname	= "use_optimistic",
6213 		.data		= &ipv6_devconf.use_optimistic,
6214 		.maxlen		= sizeof(int),
6215 		.mode		= 0644,
6216 		.proc_handler	= proc_dointvec,
6217 	},
6218 #endif
6219 #ifdef CONFIG_IPV6_MROUTE
6220 	{
6221 		.procname	= "mc_forwarding",
6222 		.data		= &ipv6_devconf.mc_forwarding,
6223 		.maxlen		= sizeof(int),
6224 		.mode		= 0444,
6225 		.proc_handler	= proc_dointvec,
6226 	},
6227 #endif
6228 	{
6229 		.procname	= "disable_ipv6",
6230 		.data		= &ipv6_devconf.disable_ipv6,
6231 		.maxlen		= sizeof(int),
6232 		.mode		= 0644,
6233 		.proc_handler	= addrconf_sysctl_disable,
6234 	},
6235 	{
6236 		.procname	= "accept_dad",
6237 		.data		= &ipv6_devconf.accept_dad,
6238 		.maxlen		= sizeof(int),
6239 		.mode		= 0644,
6240 		.proc_handler	= proc_dointvec,
6241 	},
6242 	{
6243 		.procname	= "force_tllao",
6244 		.data		= &ipv6_devconf.force_tllao,
6245 		.maxlen		= sizeof(int),
6246 		.mode		= 0644,
6247 		.proc_handler	= proc_dointvec
6248 	},
6249 	{
6250 		.procname	= "ndisc_notify",
6251 		.data		= &ipv6_devconf.ndisc_notify,
6252 		.maxlen		= sizeof(int),
6253 		.mode		= 0644,
6254 		.proc_handler	= proc_dointvec
6255 	},
6256 	{
6257 		.procname	= "suppress_frag_ndisc",
6258 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6259 		.maxlen		= sizeof(int),
6260 		.mode		= 0644,
6261 		.proc_handler	= proc_dointvec
6262 	},
6263 	{
6264 		.procname	= "accept_ra_from_local",
6265 		.data		= &ipv6_devconf.accept_ra_from_local,
6266 		.maxlen		= sizeof(int),
6267 		.mode		= 0644,
6268 		.proc_handler	= proc_dointvec,
6269 	},
6270 	{
6271 		.procname	= "accept_ra_mtu",
6272 		.data		= &ipv6_devconf.accept_ra_mtu,
6273 		.maxlen		= sizeof(int),
6274 		.mode		= 0644,
6275 		.proc_handler	= proc_dointvec,
6276 	},
6277 	{
6278 		.procname	= "stable_secret",
6279 		.data		= &ipv6_devconf.stable_secret,
6280 		.maxlen		= IPV6_MAX_STRLEN,
6281 		.mode		= 0600,
6282 		.proc_handler	= addrconf_sysctl_stable_secret,
6283 	},
6284 	{
6285 		.procname	= "use_oif_addrs_only",
6286 		.data		= &ipv6_devconf.use_oif_addrs_only,
6287 		.maxlen		= sizeof(int),
6288 		.mode		= 0644,
6289 		.proc_handler	= proc_dointvec,
6290 	},
6291 	{
6292 		.procname	= "ignore_routes_with_linkdown",
6293 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6294 		.maxlen		= sizeof(int),
6295 		.mode		= 0644,
6296 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
6297 	},
6298 	{
6299 		.procname	= "drop_unicast_in_l2_multicast",
6300 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
6301 		.maxlen		= sizeof(int),
6302 		.mode		= 0644,
6303 		.proc_handler	= proc_dointvec,
6304 	},
6305 	{
6306 		.procname	= "drop_unsolicited_na",
6307 		.data		= &ipv6_devconf.drop_unsolicited_na,
6308 		.maxlen		= sizeof(int),
6309 		.mode		= 0644,
6310 		.proc_handler	= proc_dointvec,
6311 	},
6312 	{
6313 		.procname	= "keep_addr_on_down",
6314 		.data		= &ipv6_devconf.keep_addr_on_down,
6315 		.maxlen		= sizeof(int),
6316 		.mode		= 0644,
6317 		.proc_handler	= proc_dointvec,
6318 
6319 	},
6320 	{
6321 		.procname	= "seg6_enabled",
6322 		.data		= &ipv6_devconf.seg6_enabled,
6323 		.maxlen		= sizeof(int),
6324 		.mode		= 0644,
6325 		.proc_handler	= proc_dointvec,
6326 	},
6327 #ifdef CONFIG_IPV6_SEG6_HMAC
6328 	{
6329 		.procname	= "seg6_require_hmac",
6330 		.data		= &ipv6_devconf.seg6_require_hmac,
6331 		.maxlen		= sizeof(int),
6332 		.mode		= 0644,
6333 		.proc_handler	= proc_dointvec,
6334 	},
6335 #endif
6336 	{
6337 		.procname       = "enhanced_dad",
6338 		.data           = &ipv6_devconf.enhanced_dad,
6339 		.maxlen         = sizeof(int),
6340 		.mode           = 0644,
6341 		.proc_handler   = proc_dointvec,
6342 	},
6343 	{
6344 		.procname		= "addr_gen_mode",
6345 		.data			= &ipv6_devconf.addr_gen_mode,
6346 		.maxlen			= sizeof(int),
6347 		.mode			= 0644,
6348 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
6349 	},
6350 	{
6351 		.procname       = "disable_policy",
6352 		.data           = &ipv6_devconf.disable_policy,
6353 		.maxlen         = sizeof(int),
6354 		.mode           = 0644,
6355 		.proc_handler   = addrconf_sysctl_disable_policy,
6356 	},
6357 	{
6358 		/* sentinel */
6359 	}
6360 };
6361 
6362 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
6363 		struct inet6_dev *idev, struct ipv6_devconf *p)
6364 {
6365 	int i, ifindex;
6366 	struct ctl_table *table;
6367 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
6368 
6369 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL);
6370 	if (!table)
6371 		goto out;
6372 
6373 	for (i = 0; table[i].data; i++) {
6374 		table[i].data += (char *)p - (char *)&ipv6_devconf;
6375 		/* If one of these is already set, then it is not safe to
6376 		 * overwrite either of them: this makes proc_dointvec_minmax
6377 		 * usable.
6378 		 */
6379 		if (!table[i].extra1 && !table[i].extra2) {
6380 			table[i].extra1 = idev; /* embedded; no ref */
6381 			table[i].extra2 = net;
6382 		}
6383 	}
6384 
6385 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
6386 
6387 	p->sysctl_header = register_net_sysctl(net, path, table);
6388 	if (!p->sysctl_header)
6389 		goto free;
6390 
6391 	if (!strcmp(dev_name, "all"))
6392 		ifindex = NETCONFA_IFINDEX_ALL;
6393 	else if (!strcmp(dev_name, "default"))
6394 		ifindex = NETCONFA_IFINDEX_DEFAULT;
6395 	else
6396 		ifindex = idev->dev->ifindex;
6397 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
6398 				     ifindex, p);
6399 	return 0;
6400 
6401 free:
6402 	kfree(table);
6403 out:
6404 	return -ENOBUFS;
6405 }
6406 
6407 static void __addrconf_sysctl_unregister(struct net *net,
6408 					 struct ipv6_devconf *p, int ifindex)
6409 {
6410 	struct ctl_table *table;
6411 
6412 	if (!p->sysctl_header)
6413 		return;
6414 
6415 	table = p->sysctl_header->ctl_table_arg;
6416 	unregister_net_sysctl_table(p->sysctl_header);
6417 	p->sysctl_header = NULL;
6418 	kfree(table);
6419 
6420 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
6421 }
6422 
6423 static int addrconf_sysctl_register(struct inet6_dev *idev)
6424 {
6425 	int err;
6426 
6427 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
6428 		return -EINVAL;
6429 
6430 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
6431 				    &ndisc_ifinfo_sysctl_change);
6432 	if (err)
6433 		return err;
6434 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
6435 					 idev, &idev->cnf);
6436 	if (err)
6437 		neigh_sysctl_unregister(idev->nd_parms);
6438 
6439 	return err;
6440 }
6441 
6442 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
6443 {
6444 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
6445 				     idev->dev->ifindex);
6446 	neigh_sysctl_unregister(idev->nd_parms);
6447 }
6448 
6449 
6450 #endif
6451 
6452 static int __net_init addrconf_init_net(struct net *net)
6453 {
6454 	int err = -ENOMEM;
6455 	struct ipv6_devconf *all, *dflt;
6456 
6457 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
6458 	if (!all)
6459 		goto err_alloc_all;
6460 
6461 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
6462 	if (!dflt)
6463 		goto err_alloc_dflt;
6464 
6465 	/* these will be inherited by all namespaces */
6466 	dflt->autoconf = ipv6_defaults.autoconf;
6467 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
6468 
6469 	dflt->stable_secret.initialized = false;
6470 	all->stable_secret.initialized = false;
6471 
6472 	net->ipv6.devconf_all = all;
6473 	net->ipv6.devconf_dflt = dflt;
6474 
6475 #ifdef CONFIG_SYSCTL
6476 	err = __addrconf_sysctl_register(net, "all", NULL, all);
6477 	if (err < 0)
6478 		goto err_reg_all;
6479 
6480 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
6481 	if (err < 0)
6482 		goto err_reg_dflt;
6483 #endif
6484 	return 0;
6485 
6486 #ifdef CONFIG_SYSCTL
6487 err_reg_dflt:
6488 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
6489 err_reg_all:
6490 	kfree(dflt);
6491 #endif
6492 err_alloc_dflt:
6493 	kfree(all);
6494 err_alloc_all:
6495 	return err;
6496 }
6497 
6498 static void __net_exit addrconf_exit_net(struct net *net)
6499 {
6500 #ifdef CONFIG_SYSCTL
6501 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
6502 				     NETCONFA_IFINDEX_DEFAULT);
6503 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
6504 				     NETCONFA_IFINDEX_ALL);
6505 #endif
6506 	kfree(net->ipv6.devconf_dflt);
6507 	kfree(net->ipv6.devconf_all);
6508 }
6509 
6510 static struct pernet_operations addrconf_ops = {
6511 	.init = addrconf_init_net,
6512 	.exit = addrconf_exit_net,
6513 };
6514 
6515 static struct rtnl_af_ops inet6_ops __read_mostly = {
6516 	.family		  = AF_INET6,
6517 	.fill_link_af	  = inet6_fill_link_af,
6518 	.get_link_af_size = inet6_get_link_af_size,
6519 	.validate_link_af = inet6_validate_link_af,
6520 	.set_link_af	  = inet6_set_link_af,
6521 };
6522 
6523 /*
6524  *	Init / cleanup code
6525  */
6526 
6527 int __init addrconf_init(void)
6528 {
6529 	struct inet6_dev *idev;
6530 	int i, err;
6531 
6532 	err = ipv6_addr_label_init();
6533 	if (err < 0) {
6534 		pr_crit("%s: cannot initialize default policy table: %d\n",
6535 			__func__, err);
6536 		goto out;
6537 	}
6538 
6539 	err = register_pernet_subsys(&addrconf_ops);
6540 	if (err < 0)
6541 		goto out_addrlabel;
6542 
6543 	addrconf_wq = create_workqueue("ipv6_addrconf");
6544 	if (!addrconf_wq) {
6545 		err = -ENOMEM;
6546 		goto out_nowq;
6547 	}
6548 
6549 	/* The addrconf netdev notifier requires that loopback_dev
6550 	 * has it's ipv6 private information allocated and setup
6551 	 * before it can bring up and give link-local addresses
6552 	 * to other devices which are up.
6553 	 *
6554 	 * Unfortunately, loopback_dev is not necessarily the first
6555 	 * entry in the global dev_base list of net devices.  In fact,
6556 	 * it is likely to be the very last entry on that list.
6557 	 * So this causes the notifier registry below to try and
6558 	 * give link-local addresses to all devices besides loopback_dev
6559 	 * first, then loopback_dev, which cases all the non-loopback_dev
6560 	 * devices to fail to get a link-local address.
6561 	 *
6562 	 * So, as a temporary fix, allocate the ipv6 structure for
6563 	 * loopback_dev first by hand.
6564 	 * Longer term, all of the dependencies ipv6 has upon the loopback
6565 	 * device and it being up should be removed.
6566 	 */
6567 	rtnl_lock();
6568 	idev = ipv6_add_dev(init_net.loopback_dev);
6569 	rtnl_unlock();
6570 	if (IS_ERR(idev)) {
6571 		err = PTR_ERR(idev);
6572 		goto errlo;
6573 	}
6574 
6575 	ip6_route_init_special_entries();
6576 
6577 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6578 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
6579 
6580 	register_netdevice_notifier(&ipv6_dev_notf);
6581 
6582 	addrconf_verify();
6583 
6584 	rtnl_af_register(&inet6_ops);
6585 
6586 	err = __rtnl_register(PF_INET6, RTM_GETLINK, NULL, inet6_dump_ifinfo,
6587 			      0);
6588 	if (err < 0)
6589 		goto errout;
6590 
6591 	/* Only the first call to __rtnl_register can fail */
6592 	__rtnl_register(PF_INET6, RTM_NEWADDR, inet6_rtm_newaddr, NULL, 0);
6593 	__rtnl_register(PF_INET6, RTM_DELADDR, inet6_rtm_deladdr, NULL, 0);
6594 	__rtnl_register(PF_INET6, RTM_GETADDR, inet6_rtm_getaddr,
6595 			inet6_dump_ifaddr, RTNL_FLAG_DOIT_UNLOCKED);
6596 	__rtnl_register(PF_INET6, RTM_GETMULTICAST, NULL,
6597 			inet6_dump_ifmcaddr, 0);
6598 	__rtnl_register(PF_INET6, RTM_GETANYCAST, NULL,
6599 			inet6_dump_ifacaddr, 0);
6600 	__rtnl_register(PF_INET6, RTM_GETNETCONF, inet6_netconf_get_devconf,
6601 			inet6_netconf_dump_devconf, RTNL_FLAG_DOIT_UNLOCKED);
6602 
6603 	ipv6_addr_label_rtnl_register();
6604 
6605 	return 0;
6606 errout:
6607 	rtnl_af_unregister(&inet6_ops);
6608 	unregister_netdevice_notifier(&ipv6_dev_notf);
6609 errlo:
6610 	destroy_workqueue(addrconf_wq);
6611 out_nowq:
6612 	unregister_pernet_subsys(&addrconf_ops);
6613 out_addrlabel:
6614 	ipv6_addr_label_cleanup();
6615 out:
6616 	return err;
6617 }
6618 
6619 void addrconf_cleanup(void)
6620 {
6621 	struct net_device *dev;
6622 	int i;
6623 
6624 	unregister_netdevice_notifier(&ipv6_dev_notf);
6625 	unregister_pernet_subsys(&addrconf_ops);
6626 	ipv6_addr_label_cleanup();
6627 
6628 	rtnl_af_unregister(&inet6_ops);
6629 
6630 	rtnl_lock();
6631 
6632 	/* clean dev list */
6633 	for_each_netdev(&init_net, dev) {
6634 		if (__in6_dev_get(dev) == NULL)
6635 			continue;
6636 		addrconf_ifdown(dev, 1);
6637 	}
6638 	addrconf_ifdown(init_net.loopback_dev, 2);
6639 
6640 	/*
6641 	 *	Check hash table.
6642 	 */
6643 	spin_lock_bh(&addrconf_hash_lock);
6644 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6645 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
6646 	spin_unlock_bh(&addrconf_hash_lock);
6647 	cancel_delayed_work(&addr_chk_work);
6648 	rtnl_unlock();
6649 
6650 	destroy_workqueue(addrconf_wq);
6651 }
6652